feat(t-paliad-110): refactor Dashboard rails — drop Erledigt card, add Später + Termine rail

PR-4 of the Fristen+Termine unification, closing out t-paliad-110.

Fristen rail (was 5 cards):
- Erledigt card removed (status=completed stays reachable via the EventsPage
  filter dropdown — no card on the rail per the new model)
- Später card added (pending deadlines past Mon-week-after, click filters
  to /deadlines?status=later)
- 4+1 final shape: Überfällig (conditional alarm) · Heute · Diese Woche ·
  Nächste Woche · Später

Termine rail (new): 3 cards — Heute · Diese Woche · Später. No Überfällig
(past appointments aren't urgent), no Nächste Woche (low-value distinction
for appointments per the design rationale). Cards click through to
/appointments?status=… so users land in the matching EventsPage view.

Backend (DashboardService.loadSummary):
- DeadlineSummary.CompletedThisWeek dropped, .Later added
- AppointmentSummary added (Today / ThisWeek / Later)
- One CTE-based query computes both rails alongside MatterSummary; bucket
  cutoffs share computeDeadlineBucketBounds with /api/events/summary +
  /api/deadlines/summary so all three surfaces stay in lockstep

Frontend:
- dashboard.tsx: Erledigt card removed, Später card + Termine section added
- client/dashboard.ts: types updated, renderAppointmentSummary added
- 4 new i18n keys (DE+EN): dashboard.summary.later +
  dashboard.appointment_summary.heading
- CSS: .dashboard-card-later (muted blue) + 3 .dashboard-card-appt-* rules
  reusing the existing --bucket-* tokens

go build/vet/test ./... clean. bun run build clean (1396 keys).

frontend/src/client/dashboard.ts

@@ -14,7 +14,13 @@ interface DeadlineSummary {
   today: number;
   this_week: number;
   next_week: number;
-  completed_this_week: number;
+  later: number;
+}
+
+interface AppointmentSummary {
+  today: number;
+  this_week: number;
+  later: number;
 }
 
 interface MatterSummary {
@@ -60,6 +66,7 @@ interface ActivityEntry {
 interface DashboardData {
   user: DashboardUser | null;
   deadline_summary: DeadlineSummary;
+  appointment_summary: AppointmentSummary;
   matter_summary: MatterSummary;
   upcoming_deadlines: UpcomingDeadline[];
   upcoming_appointments: UpcomingAppointment[];
@@ -98,6 +105,7 @@ function render(): void {
   if (!data) return;
   renderGreeting(data.user);
   renderSummary(data.deadline_summary);
+  renderAppointmentSummary(data.appointment_summary);
   renderMatters(data.matter_summary);
   renderDeadlines(data.upcoming_deadlines);
   renderAppointments(data.upcoming_appointments);
@@ -133,17 +141,23 @@ function renderSummary(s: DeadlineSummary): void {
   setCount("dashboard-count-today", s.today);
   setCount("dashboard-count-this-week", s.this_week);
   setCount("dashboard-count-next-week", s.next_week);
-  setCount("dashboard-count-completed", s.completed_this_week);
+  setCount("dashboard-count-later", s.later);
 
   // Überfällig is an emergency category — hide the card entirely on a clean
   // slate (the .dashboard-summary-grid uses auto-fit so the row re-flows to
   // 4 cards) and trip the alarm styling when there's anything overdue. See
-  // t-paliad-105 / t-paliad-106.
+  // t-paliad-105 / t-paliad-106 / t-paliad-110.
   const overdueCard = document.getElementById("dashboard-card-overdue")!;
   overdueCard.classList.toggle("dashboard-card-overdue-hidden", s.overdue === 0);
   overdueCard.classList.toggle("dashboard-card-alarm", s.overdue > 0);
 }
 
+function renderAppointmentSummary(s: AppointmentSummary): void {
+  setCount("dashboard-count-appt-today", s.today);
+  setCount("dashboard-count-appt-this-week", s.this_week);
+  setCount("dashboard-count-appt-later", s.later);
+}
+
 function renderMatters(s: MatterSummary): void {
   setCount("dashboard-matter-active", s.active);
   setCount("dashboard-matter-archived", s.archived);

frontend/src/client/i18n.ts

@@ -667,6 +667,8 @@ const translations: Record<Lang, Record<string, string>> = {
     "dashboard.summary.this_week": "Diese Woche",
     "dashboard.summary.next_week": "N\u00e4chste Woche",
     "dashboard.summary.completed": "Erledigt",
+    "dashboard.summary.later": "Später",
+    "dashboard.appointment_summary.heading": "Termine auf einen Blick",
     "dashboard.matters.heading": "Meine Akten",
     "dashboard.matters.active": "Aktiv",
     "dashboard.matters.archived": "Archiviert",
@@ -2165,6 +2167,8 @@ const translations: Record<Lang, Record<string, string>> = {
     "dashboard.summary.this_week": "This week",
     "dashboard.summary.next_week": "Next week",
     "dashboard.summary.completed": "Done",
+    "dashboard.summary.later": "Later",
+    "dashboard.appointment_summary.heading": "Appointments at a glance",
     "dashboard.matters.heading": "My matters",
     "dashboard.matters.active": "Active",
     "dashboard.matters.archived": "Archived",

frontend/src/dashboard.tsx

@@ -57,7 +57,7 @@ export function renderDashboard(): string {
                 </p>
               </div>
 
-              {/* Traffic-light deadline summary */}
+              {/* Traffic-light deadline summary (4+1: Überfällig conditional + 4 universal — t-paliad-110) */}
               <section className="dashboard-summary" aria-labelledby="dashboard-summary-heading">
                 <h2 id="dashboard-summary-heading" className="dashboard-section-heading" data-i18n="dashboard.summary.heading">
                   Fristen auf einen Blick
@@ -79,9 +79,30 @@ export function renderDashboard(): string {
                     <div className="dashboard-card-count" id="dashboard-count-next-week">0</div>
                     <div className="dashboard-card-label" data-i18n="dashboard.summary.next_week">N&auml;chste Woche</div>
                   </a>
-                  <a href="/deadlines?status=completed" className="dashboard-card dashboard-card-done" id="dashboard-card-completed">
-                    <div className="dashboard-card-count" id="dashboard-count-completed">0</div>
-                    <div className="dashboard-card-label" data-i18n="dashboard.summary.completed">Erledigt</div>
+                  <a href="/deadlines?status=later" className="dashboard-card dashboard-card-later" id="dashboard-card-later">
+                    <div className="dashboard-card-count" id="dashboard-count-later">0</div>
+                    <div className="dashboard-card-label" data-i18n="dashboard.summary.later">Sp&auml;ter</div>
+                  </a>
+                </div>
+              </section>
+
+              {/* Termine summary rail — 3 cards: Heute · Diese Woche · Später (t-paliad-110) */}
+              <section className="dashboard-summary" aria-labelledby="dashboard-appointment-summary-heading">
+                <h2 id="dashboard-appointment-summary-heading" className="dashboard-section-heading" data-i18n="dashboard.appointment_summary.heading">
+                  Termine auf einen Blick
+                </h2>
+                <div className="dashboard-summary-grid">
+                  <a href="/appointments?status=today" className="dashboard-card dashboard-card-appt-today" id="dashboard-card-appt-today">
+                    <div className="dashboard-card-count" id="dashboard-count-appt-today">0</div>
+                    <div className="dashboard-card-label" data-i18n="dashboard.summary.today">Heute</div>
+                  </a>
+                  <a href="/appointments?status=this_week" className="dashboard-card dashboard-card-appt-week" id="dashboard-card-appt-thisweek">
+                    <div className="dashboard-card-count" id="dashboard-count-appt-this-week">0</div>
+                    <div className="dashboard-card-label" data-i18n="dashboard.summary.this_week">Diese Woche</div>
+                  </a>
+                  <a href="/appointments?status=later" className="dashboard-card dashboard-card-appt-later" id="dashboard-card-appt-later">
+                    <div className="dashboard-card-count" id="dashboard-count-appt-later">0</div>
+                    <div className="dashboard-card-label" data-i18n="dashboard.summary.later">Sp&auml;ter</div>
                   </a>
                 </div>
               </section>

frontend/src/i18n-keys.ts

@@ -505,6 +505,7 @@ export type I18nKey =
   | "dashboard.activity.event"
   | "dashboard.activity.heading"
   | "dashboard.activity.system"
+  | "dashboard.appointment_summary.heading"
   | "dashboard.appointments.empty"
   | "dashboard.appointments.heading"
   | "dashboard.deadlines.empty"
@@ -517,6 +518,7 @@ export type I18nKey =
   | "dashboard.onboarding"
   | "dashboard.summary.completed"
   | "dashboard.summary.heading"
+  | "dashboard.summary.later"
   | "dashboard.summary.next_week"
   | "dashboard.summary.overdue"
   | "dashboard.summary.this_week"

frontend/src/styles/global.css

@@ -5702,6 +5702,17 @@ input[type="range"]::-moz-range-thumb {
 .dashboard-card-green                       { border-left: 3px solid var(--bucket-next-week); }
 .dashboard-card-done .dashboard-card-count  { color: var(--bucket-done); }
 .dashboard-card-done                        { border-left: 3px solid var(--bucket-done); }
+/* Später bucket on the Fristen rail — muted blue (t-paliad-110). */
+.dashboard-card-later .dashboard-card-count { color: var(--bucket-later); }
+.dashboard-card-later                       { border-left: 3px solid var(--bucket-later); }
+/* Termine rail uses the same urgency token family — keep the palette
+   consistent across rails so users read both at the same glance. */
+.dashboard-card-appt-today .dashboard-card-count { color: var(--bucket-today); }
+.dashboard-card-appt-today                       { border-left: 3px solid var(--bucket-today); }
+.dashboard-card-appt-week  .dashboard-card-count { color: var(--bucket-week); }
+.dashboard-card-appt-week                        { border-left: 3px solid var(--bucket-week); }
+.dashboard-card-appt-later .dashboard-card-count { color: var(--bucket-later); }
+.dashboard-card-appt-later                       { border-left: 3px solid var(--bucket-later); }
 
 /* Überfällig alarm — see t-paliad-105 / t-paliad-106.
    When overdue > 0 the card flips from a calm border-left accent to a