Merge: t-paliad-165 — Regel ↔ Typ collapse via auto-link on the deadline create form

Two slices on mai/noether/collapse-regel-typ-on:

  0c12644  feat(deadline-rules): expose concept's canonical event_type per rule
  1e97ecc  feat(deadlines/new): auto-link Typ to Regel's concept

What ships:

- New junction paliad.deadline_concept_event_types maps every
  paliad.deadline_concepts row to its canonical paliad.event_types
  row(s). Many-to-many for concepts with multiple legitimate variants
  (statement-of-defence ↔ base + with_ccr + no_ccr; opposition across
  EPO + DPMA). Exactly one row per concept marked is_default = true
  by a partial unique index — that is the row the deadline form
  auto-fills with.

- Backend: paliad.deadline_rules_with_concept_event_type view + the
  deadline-rules read path now expose the rule's default concept
  event_type so the form has the auto-fill target without an extra
  round-trip.

- Frontend deadline create / edit form: when the user picks a Regel,
  the Typ chip auto-fills with the rule's concept's default event_type.
  A small "vorgegeben durch Regel — überschreiben?" hint sits next to
  the chip so the auto-fill is visible. The user can override (free-
  text or pick a different type); the override is explicit, no
  blocking validation.

- Free-text Typ stays available — manual deadlines without a
  matching rule (e.g. "Call me" reminders) keep working as today.

Migration housekeeping
======================

noether authored her migration as 072 on her branch but main had
already taken 072 via minkowski's t-paliad-164 (paliad.projects.our_side).
Renumbered to 073 during merge resolution to resolve the same-number
collision. Added IF NOT EXISTS guards on CREATE TABLE / CREATE INDEX
for re-run safety (the seed INSERT already had ON CONFLICT DO NOTHING).

Live tracker bumped 72 → 73 in the same operation: both effects
(our_side column AND deadline_concept_event_types table) were
applied to live during dev (each worker against the same DB), so
the tracker advance reflects schema reality. Next deploy sees
tracker=73 with file 073 present and has nothing to apply.

Refs m/paliad#18.

internal/services/deadline_rule_service.go

@@ -32,6 +32,9 @@ const proceedingTypeColumns = `id, code, name, name_en, description, jurisdictio
 	category, default_color, sort_order, is_active`
 
 // List returns active rules, optionally filtered by proceeding type.
+// Each row has ConceptDefaultEventTypeID hydrated from
+// paliad.deadline_concept_event_types so the deadline-create form can
+// auto-populate the Typ chip when the user picks a Regel.
 func (s *DeadlineRuleService) List(ctx context.Context, proceedingTypeID *int) ([]models.DeadlineRule, error) {
 	var rules []models.DeadlineRule
 	var err error
@@ -52,9 +55,62 @@ func (s *DeadlineRuleService) List(ctx context.Context, proceedingTypeID *int) (
 	if err != nil {
 		return nil, fmt.Errorf("list deadline rules: %w", err)
 	}
+	if err := s.hydrateConceptDefaultEventTypes(ctx, rules); err != nil {
+		return nil, err
+	}
 	return rules, nil
 }
 
+// hydrateConceptDefaultEventTypes resolves rule.ConceptID →
+// paliad.deadline_concept_event_types.event_type_id (where is_default)
+// for every rule with a non-nil ConceptID, and assigns the result.
+// One round-trip; rules whose concept has no default mapping stay NULL.
+func (s *DeadlineRuleService) hydrateConceptDefaultEventTypes(ctx context.Context, rules []models.DeadlineRule) error {
+	conceptIDs := make([]uuid.UUID, 0, len(rules))
+	seen := make(map[uuid.UUID]bool, len(rules))
+	for _, r := range rules {
+		if r.ConceptID == nil || seen[*r.ConceptID] {
+			continue
+		}
+		seen[*r.ConceptID] = true
+		conceptIDs = append(conceptIDs, *r.ConceptID)
+	}
+	if len(conceptIDs) == 0 {
+		return nil
+	}
+	query, args, err := sqlx.In(
+		`SELECT concept_id, event_type_id
+		   FROM paliad.deadline_concept_event_types
+		  WHERE is_default = true AND concept_id IN (?)`, conceptIDs)
+	if err != nil {
+		return fmt.Errorf("build concept→event_type IN query: %w", err)
+	}
+	query = s.db.Rebind(query)
+
+	type row struct {
+		ConceptID   uuid.UUID `db:"concept_id"`
+		EventTypeID uuid.UUID `db:"event_type_id"`
+	}
+	var rows []row
+	if err := s.db.SelectContext(ctx, &rows, query, args...); err != nil {
+		return fmt.Errorf("load concept→event_type defaults: %w", err)
+	}
+	defaultByConcept := make(map[uuid.UUID]uuid.UUID, len(rows))
+	for _, r := range rows {
+		defaultByConcept[r.ConceptID] = r.EventTypeID
+	}
+	for i := range rules {
+		if rules[i].ConceptID == nil {
+			continue
+		}
+		if et, ok := defaultByConcept[*rules[i].ConceptID]; ok {
+			etCopy := et
+			rules[i].ConceptDefaultEventTypeID = &etCopy
+		}
+	}
+	return nil
+}
+
 // RuleTreeNode pairs a rule with its child rules in a parent_id hierarchy.
 type RuleTreeNode struct {
 	models.DeadlineRule