feat(ui): canvas zoom + pan via SVG viewBox

m: wheel to zoom around the cursor, drag with middle-mouse / Space-held
to pan, `0` or `Home` to reset, Fit button to frame all content.

Implementation:
- state.view = { x, y, zoom } drives the SVG viewBox via applyViewBox().
  Base canvas is 2000×1500; viewBox = (view.x, view.y, 2000/zoom, 1500/zoom).
- Zoom clamped to 0.2x..5x. wheelZoom captures the cursor's world coord
  before + after the zoom-step and shifts view.x/y so it stays under
  the cursor (Excalidraw-style cursor-anchored zoom).
- startPan captures screen→world scale from getScreenCTM at pointerdown
  and converts pointer-move deltas into view.x/y updates — robust across
  zoom levels. Triggered by middle-mouse OR Space+drag. Releases pointer
  capture + persists the view on pointerup.
- resetView (0 / Home) restores zoom=1, x=0, y=0.
- fitToContent walks frames + devices + IO markers, computes their bbox
  with 40px padding, picks zoom = min(BASE_W/bw, BASE_H/bh), and centres
  the bbox inside the viewBox (compensating for aspect-ratio meet).
- Header gets a "100%" zoom indicator + Fit button. URL persists view
  as ?z=1.200&px=…&py=… so reload returns to the same view.

Because everything goes through viewBox (not CSS transform), svgPoint
still maps screen pixels to world coords via getScreenCTM. Existing
hit-tests, drag, port/cable placement all keep working unchanged.

internal/db/models.go

@@ -191,10 +191,11 @@ type UnsatisfiedReq struct {
 
 // ApplyTemplateResult is the response from POST /apply-template.
 type ApplyTemplateResult struct {
-	DevicesAdded         []Device                `json:"devices_added"`
-	RequirementsAdded    []ConnectionRequirement `json:"requirements_added"`
-	SkippedDevices       []SkippedTemplateDevice `json:"skipped_devices"`
-	RequirementsSkipped  []SkippedTemplateReq    `json:"requirements_skipped"`
+	FramesAdded         []Frame                 `json:"frames_added"`
+	DevicesAdded        []Device                `json:"devices_added"`
+	RequirementsAdded   []ConnectionRequirement `json:"requirements_added"`
+	SkippedDevices      []SkippedTemplateDevice `json:"skipped_devices"`
+	RequirementsSkipped []SkippedTemplateReq    `json:"requirements_skipped"`
 }
 
 type SkippedTemplateDevice struct {

internal/db/setup_templates.go

@@ -4,6 +4,7 @@ import (
 	"database/sql"
 	"errors"
 	"fmt"
+	"math"
 	"strings"
 )
 
@@ -161,6 +162,7 @@ func (s *Store) ApplyTemplate(projectID, templateID int64, opts ApplyTemplateOpt
 	}
 
 	out := &ApplyTemplateResult{
+		FramesAdded:         []Frame{},
 		DevicesAdded:        []Device{},
 		RequirementsAdded:   []ConnectionRequirement{},
 		SkippedDevices:      []SkippedTemplateDevice{},
@@ -171,8 +173,8 @@ func (s *Store) ApplyTemplate(projectID, templateID int64, opts ApplyTemplateOpt
 		opts.OriginX, opts.OriginY = 200, 200
 	}
 
-	// Pull existing device names in the project so we can pre-check
-	// collisions without aborting the whole transaction.
+	// Pull existing device + frame names in the project so we can
+	// pre-check collisions without aborting the whole transaction.
 	existing, err := s.ListDevices(projectID, nil)
 	if err != nil {
 		return nil, err
@@ -181,6 +183,14 @@ func (s *Store) ApplyTemplate(projectID, templateID int64, opts ApplyTemplateOpt
 	for _, d := range existing {
 		nameTaken[d.Name] = true
 	}
+	existingFrames, err := s.ListFrames(projectID)
+	if err != nil {
+		return nil, err
+	}
+	frameNameTaken := map[string]bool{}
+	for _, f := range existingFrames {
+		frameNameTaken[f.Name] = true
+	}
 
 	tx, err := s.db.Begin()
 	if err != nil {
@@ -188,6 +198,37 @@ func (s *Store) ApplyTemplate(projectID, templateID int64, opts ApplyTemplateOpt
 	}
 	defer tx.Rollback()
 
+	// Plan a uniform grid for the template's devices inside a new frame
+	// named after the template. The grid drives both frame size and
+	// per-device (x, y). Devices that get skipped (name collision /
+	// SkipDevices) leave their grid cell empty.
+	const (
+		devW, devH = 100.0, 35.0
+		gapX, gapY = 30.0, 50.0
+		padX, padY = 32.0, 48.0 // padY larger so the frame title clears row 1
+	)
+	n := len(tmpl.Devices)
+	cols := 1
+	if n > 0 {
+		cols = min(int(math.Ceil(math.Sqrt(float64(n)))), 4)
+	}
+	rows := 1
+	if n > 0 {
+		rows = (n + cols - 1) / cols
+	}
+	frameW := padX*2 + float64(cols)*devW + float64(cols-1)*gapX
+	frameH := padY + padX + float64(rows)*devH + float64(rows-1)*gapY
+	frameName := pickFrameName(tmpl.Name, frameNameTaken)
+
+	frame, err := createFrameTx(tx, projectID, FrameCreate{
+		Name: frameName, X: opts.OriginX, Y: opts.OriginY,
+		Width: frameW, Height: frameH,
+	})
+	if err != nil {
+		return nil, fmt.Errorf("seed frame %q: %w", frameName, err)
+	}
+	out.FramesAdded = append(out.FramesAdded, *frame)
+
 	// Map: template_device_id → newly-created device_id (or 0 if skipped).
 	tmplToDevice := map[int64]int64{}
 
@@ -215,17 +256,22 @@ func (s *Store) ApplyTemplate(projectID, templateID int64, opts ApplyTemplateOpt
 			tmplToDevice[td.ID] = 0
 			continue
 		}
-		// Lay out devices in a horizontal row near the origin, 150 px apart.
-		x := opts.OriginX + float64(i)*150
-		y := opts.OriginY
-		// Use createDeviceTx so the port-seeding share the same transaction.
+		// Grid cell (col, row) within the frame. Cell anchor is the
+		// top-left of the device rect; offsets are added to the frame's
+		// own (x, y) so the device sits inside the frame.
+		col := i % cols
+		row := i / cols
+		x := frame.X + padX + float64(col)*(devW+gapX)
+		y := frame.Y + padY + float64(row)*(devH+gapY)
+		// Use createDeviceTx so port-seeding shares the same transaction.
 		d, err := s.createDeviceTx(tx, projectID, DeviceCreate{
 			Name:    name,
 			TypeID:  &td.DeviceTypeID,
+			FrameID: &frame.ID,
 			X:       x,
 			Y:       y,
-			Width:   100,
-			Height:  35,
+			Width:   devW,
+			Height:  devH,
 		})
 		if err != nil {
 			return nil, fmt.Errorf("seed %s: %w", name, err)
@@ -294,6 +340,58 @@ func (s *Store) ApplyTemplate(projectID, templateID int64, opts ApplyTemplateOpt
 	return out, nil
 }
 
+// pickFrameName returns a frame name that doesn't collide with anything
+// in `taken`. Tries the template name first, then "<name> 2", "<name> 3",
+// and so on.
+func pickFrameName(base string, taken map[string]bool) string {
+	if !taken[base] {
+		return base
+	}
+	for i := 2; ; i++ {
+		candidate := fmt.Sprintf("%s %d", base, i)
+		if !taken[candidate] {
+			return candidate
+		}
+	}
+}
+
+// createFrameTx inserts a frame inside the caller's transaction. Mirrors
+// the validation in CreateFrame (name + positive size) but avoids the
+// s.db.Exec call so ApplyTemplate can keep everything on the same
+// connection under MaxOpenConns(1).
+func createFrameTx(tx *sql.Tx, projectID int64, f FrameCreate) (*Frame, error) {
+	name := strings.TrimSpace(f.Name)
+	if name == "" {
+		return nil, fmt.Errorf("%w: name is required", ErrInvalidInput)
+	}
+	if f.Width <= 0 || f.Height <= 0 {
+		return nil, fmt.Errorf("%w: width and height must be positive", ErrInvalidInput)
+	}
+	res, err := tx.Exec(
+		`INSERT INTO frames (project_id, name, x, y, width, height)
+		 VALUES (?, ?, ?, ?, ?, ?)`,
+		projectID, name, f.X, f.Y, f.Width, f.Height,
+	)
+	if err != nil {
+		return nil, mapWriteErr(err)
+	}
+	id, _ := res.LastInsertId()
+	var out Frame
+	var ex sql.NullString
+	err = tx.QueryRow(
+		`SELECT id, project_id, name, x, y, width, height, excalidraw_id, created_at, updated_at
+		 FROM frames WHERE id = ? AND project_id = ?`, id, projectID,
+	).Scan(&out.ID, &out.ProjectID, &out.Name, &out.X, &out.Y, &out.Width, &out.Height,
+		&ex, &out.CreatedAt, &out.UpdatedAt)
+	if err != nil {
+		return nil, err
+	}
+	if ex.Valid {
+		out.ExcalidrawID = &ex.String
+	}
+	return &out, nil
+}
+
 // createDeviceTx is a tx-aware variant of CreateDevice used by
 // ApplyTemplate so seeding the template's devices + their ports stays
 // inside one atomic apply.

internal/db/solver_test.go

@@ -234,6 +234,76 @@ func TestApplyTemplate_HomeOffice_ThenSolve(t *testing.T) {
 	}
 }
 
+func TestApplyTemplate_CreatesFrameAndPlacesDevicesInside(t *testing.T) {
+	s := newTestStore(t)
+	p, _ := s.CreateProject("LOFT", "", "")
+	tmpls, _ := s.ListSetupTemplates()
+	var lr SetupTemplate
+	for _, tm := range tmpls {
+		if tm.Name == "Living Room" {
+			lr = tm
+			break
+		}
+	}
+	res, err := s.ApplyTemplate(p.ID, lr.ID, ApplyTemplateOptions{})
+	if err != nil {
+		t.Fatalf("apply: %v", err)
+	}
+	if len(res.FramesAdded) != 1 {
+		t.Fatalf("frames added = %d, want 1", len(res.FramesAdded))
+	}
+	frame := res.FramesAdded[0]
+	if frame.Name != "Living Room" {
+		t.Errorf("frame name = %q, want %q", frame.Name, "Living Room")
+	}
+	for _, d := range res.DevicesAdded {
+		if d.FrameID == nil || *d.FrameID != frame.ID {
+			t.Errorf("device %q: frame_id = %v, want %d", d.Name, d.FrameID, frame.ID)
+		}
+		// Device top-left should be inside the frame rect.
+		if d.X < frame.X || d.X+d.Width > frame.X+frame.Width {
+			t.Errorf("device %q: x=%v width=%v outside frame [%v..%v]", d.Name, d.X, d.Width, frame.X, frame.X+frame.Width)
+		}
+		if d.Y < frame.Y || d.Y+d.Height > frame.Y+frame.Height {
+			t.Errorf("device %q: y=%v height=%v outside frame [%v..%v]", d.Name, d.Y, d.Height, frame.Y, frame.Y+frame.Height)
+		}
+	}
+	// No two devices share the same (X, Y) — the grid layout spreads them out.
+	seen := map[[2]float64]string{}
+	for _, d := range res.DevicesAdded {
+		key := [2]float64{d.X, d.Y}
+		if prev, ok := seen[key]; ok {
+			t.Errorf("devices %q and %q share grid cell (%v, %v)", prev, d.Name, d.X, d.Y)
+		}
+		seen[key] = d.Name
+	}
+}
+
+func TestApplyTemplate_FrameNameSuffixOnCollision(t *testing.T) {
+	s := newTestStore(t)
+	p, _ := s.CreateProject("LOFT", "", "")
+	// Pre-create a frame called "Living Room" so the template's frame name collides.
+	_, _ = s.CreateFrame(p.ID, FrameCreate{Name: "Living Room", X: 0, Y: 0, Width: 100, Height: 100})
+	tmpls, _ := s.ListSetupTemplates()
+	var lr SetupTemplate
+	for _, tm := range tmpls {
+		if tm.Name == "Living Room" {
+			lr = tm
+			break
+		}
+	}
+	res, err := s.ApplyTemplate(p.ID, lr.ID, ApplyTemplateOptions{})
+	if err != nil {
+		t.Fatalf("apply: %v", err)
+	}
+	if len(res.FramesAdded) != 1 {
+		t.Fatalf("frames added = %d, want 1", len(res.FramesAdded))
+	}
+	if res.FramesAdded[0].Name != "Living Room 2" {
+		t.Errorf("frame name = %q, want %q (suffixed)", res.FramesAdded[0].Name, "Living Room 2")
+	}
+}
+
 func TestApplyTemplate_NameCollisionSkipped(t *testing.T) {
 	s := newTestStore(t)
 	p, _ := s.CreateProject("LOFT", "", "")

web/static/index.html

@@ -23,6 +23,11 @@
     <button type="button" id="btn-apply-template" class="btn">Apply template…</button>
     <button type="button" id="btn-solve" class="btn btn-primary">Solve</button>
     <button type="button" id="btn-export" class="btn">Export</button>
+    <button type="button" id="btn-admin" class="btn" title="Admin: projects, cable types, device types, setup templates">⚙ Admin</button>
+    <span class="zoom-cluster">
+      <span id="zoom-pct" title="Zoom — scroll on canvas, or 0/Home to reset">100%</span>
+      <button type="button" id="btn-fit" class="btn btn-tiny" title="Fit content to view">Fit</button>
+    </span>
     <span id="toast" class="toast" hidden></span>
   </header>
 
@@ -33,11 +38,6 @@
         <ul id="legend-list" class="legend-list"></ul>
         <button type="button" id="btn-add-type" class="btn btn-tiny">+ Type</button>
       </section>
-      <section class="requirements">
-        <h2 class="sidebar-heading">Requirements</h2>
-        <ul id="requirement-list" class="requirement-list"></ul>
-        <button type="button" id="btn-add-requirement" class="btn btn-tiny">+ Requirement</button>
-      </section>
       <section class="tools">
         <h2 class="sidebar-heading">Tools</h2>
         <ul class="tool-list">
@@ -224,6 +224,24 @@
     </form>
   </dialog>
 
+  <!-- Admin: projects + cable types + device types + setup templates -->
+  <dialog id="modal-admin" class="modal modal-wide" aria-labelledby="adm-title">
+    <div class="admin-shell">
+      <header class="admin-header">
+        <h2 id="adm-title">Admin</h2>
+        <button type="button" class="btn btn-link admin-close" data-close>✕</button>
+      </header>
+      <nav class="admin-tabs" role="tablist">
+        <button type="button" class="admin-tab" data-admin-tab="projects" role="tab" aria-selected="true">Projects</button>
+        <button type="button" class="admin-tab" data-admin-tab="cable-types" role="tab">Cable types</button>
+        <button type="button" class="admin-tab" data-admin-tab="device-types" role="tab">Device types</button>
+        <button type="button" class="admin-tab" data-admin-tab="setup-templates" role="tab">Setup templates</button>
+        <button type="button" class="admin-tab" data-admin-tab="requirements" role="tab">Requirements</button>
+      </nav>
+      <section class="admin-body" id="admin-body" role="tabpanel"></section>
+    </div>
+  </dialog>
+
   <script type="module" src="/main.js"></script>
 </body>
 </html>

web/static/style.css

@@ -183,9 +183,10 @@ body {
   pointer-events: none;
 }
 
+/* Stroke + fill come from the device's user-set colour, written as
+   inline style in renderCanvas — leaving them out of .device-rect so
+   the author CSS doesn't override the inline style. */
 .device-rect {
-  fill: #fff;
-  stroke: var(--text);
   stroke-width: 1.5;
 }
 .device-rect.selected { stroke-width: 3; }
@@ -214,8 +215,6 @@ body {
 .canvas-wrap.tool-device #canvas *,
 .canvas-wrap.tool-io     #canvas,
 .canvas-wrap.tool-io     #canvas *,
-.canvas-wrap.tool-port   #canvas,
-.canvas-wrap.tool-port   #canvas *,
 .canvas-wrap.tool-cable  #canvas,
 .canvas-wrap.tool-cable  #canvas * { cursor: crosshair !important; }
 
@@ -236,6 +235,27 @@ body {
   filter: drop-shadow(0 0 4px var(--accent));
 }
 
+/* Zoom cluster — % + Fit button next to Admin. */
+.zoom-cluster {
+  display: inline-flex;
+  align-items: center;
+  gap: 6px;
+  margin-left: 8px;
+  padding-left: 12px;
+  border-left: 1px solid var(--border);
+}
+#zoom-pct {
+  font-size: 12px;
+  color: var(--text-muted);
+  min-width: 38px;
+  text-align: right;
+  font-variant-numeric: tabular-nums;
+}
+.canvas-wrap.panning #canvas,
+.canvas-wrap.panning #canvas * { cursor: grabbing !important; }
+.canvas-wrap.space-pan-ready #canvas,
+.canvas-wrap.space-pan-ready #canvas * { cursor: grab !important; }
+
 /* Header toast — slice 8 export feedback */
 .toast {
   display: inline-block;
@@ -295,8 +315,11 @@ body {
   align-items: center;
   gap: 6px;
   font-size: 12px;
-  padding: 2px 0;
+  padding: 2px 4px;
+  border-radius: 4px;
+  cursor: pointer;
 }
+.port-row:hover { background: var(--surface-2); }
 .port-row .swatch,
 .swatch {
   display: inline-block;
@@ -374,6 +397,108 @@ body {
 
 /* Solve preview-diff modal */
 .modal-wide { width: 560px; }
+
+/* Admin modal — wider, tabbed */
+.modal-wide.admin-shell-host { width: 760px; }
+#modal-admin { width: 760px; max-width: 90vw; }
+.admin-shell { padding: 16px; min-height: 460px; }
+.admin-header {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  margin-bottom: 12px;
+}
+.admin-header h2 { margin: 0; }
+.admin-close { font-size: 16px; padding: 4px 8px; }
+.admin-tabs {
+  display: flex;
+  gap: 2px;
+  border-bottom: 1px solid var(--border);
+  margin-bottom: 12px;
+}
+.admin-tab {
+  background: transparent;
+  border: 0;
+  border-bottom: 2px solid transparent;
+  padding: 8px 12px;
+  font: inherit;
+  color: var(--text-muted);
+  cursor: pointer;
+}
+.admin-tab:hover { color: var(--text); }
+.admin-tab[aria-selected="true"] {
+  color: var(--text);
+  border-bottom-color: var(--accent);
+}
+.admin-body {
+  font-size: 13px;
+  max-height: 60vh;
+  overflow-y: auto;
+}
+.admin-row {
+  display: grid;
+  gap: 6px 12px;
+  padding: 8px 0;
+  border-bottom: 1px solid var(--border);
+}
+.admin-row:last-child { border-bottom: 0; }
+.admin-row .field { display: grid; grid-template-columns: 110px 1fr; align-items: center; }
+.admin-row .field span { color: var(--text-muted); font-size: 12px; }
+.admin-row .field input,
+.admin-row .field textarea,
+.admin-row .field select {
+  width: 100%;
+  font: inherit;
+  padding: 4px 6px;
+  border: 1px solid var(--border);
+  border-radius: 4px;
+  background: var(--bg);
+  color: var(--text);
+}
+.admin-row .actions { display: flex; gap: 6px; justify-content: flex-end; }
+.admin-row.locked { opacity: 0.85; }
+.admin-row .locked-badge {
+  display: inline-block;
+  font-size: 11px;
+  padding: 1px 6px;
+  border-radius: 3px;
+  background: var(--surface-2);
+  color: var(--text-muted);
+}
+.admin-row-title {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  font-weight: 600;
+  margin-bottom: 4px;
+}
+.admin-row-title .swatch { display: inline-block; }
+.admin-empty { color: var(--text-muted); padding: 16px 0; }
+.admin-add-row {
+  margin-top: 12px;
+  padding-top: 12px;
+  border-top: 1px solid var(--border);
+}
+.port-profile-list {
+  margin: 4px 0 0 0;
+  padding: 0;
+  list-style: none;
+  font-size: 12px;
+  color: var(--text-muted);
+}
+.port-profile-list li {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  padding: 2px 0;
+}
+.tmpl-detail {
+  margin: 4px 0 0 0;
+  font-size: 12px;
+  color: var(--text-muted);
+}
+.tmpl-detail ul { margin: 4px 0 0 16px; padding: 0; }
+
 .sv-body { font-size: 13px; }
 .sv-body h3 {
   font-size: 11px;