feat(t-paliad-088): Event Types for deadlines — schema + service + handlers (PR-1)

Migration 030 adds paliad.event_types and paliad.deadline_event_types
junction. ~43 firm-wide seeds biased toward submissions (25 UPC
submissions + 8 UPC decisions/orders/hearings + 5 EPO + 4 DPMA/DE + 1
cross-jurisdiction). UPC-seeded rows carry a loose trigger_event_id
column (no FK constraint per Q2: event_types leads, trigger_events
follows). RLS policies are defense-in-depth — primary enforcement is
in the Go service layer. Per Q6, any authenticated user can create
firm-wide types; admins moderate via the soft-delete archive lever.

EventTypeService: List (firm-wide ∪ own-private), GetByID, Create
(slug auto-derived, supports diacritics → ASCII), Update (author OR
admin-on-firm-wide), SuggestSimilar (powers the duplicate-warning in
the add modal), AttachToDeadlineTx + ValidateForUser + ListForDeadlines
for the junction.

DeadlineService gains an EventTypeService dependency and now:
- accepts event_type_ids on Create / Update / CreateBulk
- attaches them in the same transaction as the deadline insert
- hydrates EventTypeIDs on every Get / List / ListForProject
- supports the multi-select Typ filter via ListFilter.EventTypeIDs +
  IncludeUntyped (UNION semantics within types, AND-intersected with
  Status/Project)

AgendaService gets the same Typ filter on its deadline side;
appointments are unaffected.

API:
- GET /api/event-types?category=&jurisdiction=
- GET /api/event-types/suggest?q=
- POST /api/event-types
- PATCH /api/event-types/{id}        (set archive=true to hide)
- GET /api/deadlines?event_type=<uuid>,<uuid>,none
- GET /api/agenda?event_type=<uuid>,<uuid>,none
- POST/PATCH /api/deadlines accept event_type_ids: [uuid]

go build / go vet / go test ./... clean.

Frontend (picker + custom-add modal + multi-select filter) follows in
PR-2. Admin moderation panel deferred to t-paliad-089 follow-up.

cmd/server/main.go

@@ -118,12 +118,13 @@ func main() {
 		emailTemplateSvc := services.NewEmailTemplateService(pool)
 		mailSvc.SetTemplateService(emailTemplateSvc)
 
+		eventTypeSvc := services.NewEventTypeService(pool, users)
 		svcBundle = &handlers.Services{
 			Project:        projectSvc,
 			Team:           teamSvc,
 			PartnerUnit:    partnerUnitSvc,
 			Party:          services.NewPartyService(pool, projectSvc),
-			Deadline:       services.NewDeadlineService(pool, projectSvc),
+			Deadline:       services.NewDeadlineService(pool, projectSvc, eventTypeSvc),
 			Appointment:    appointmentSvc,
 			CalDAV:         caldavSvc,
 			Rules:          rules,
@@ -131,12 +132,13 @@ func main() {
 			Users:          users,
 			Fristenrechner: services.NewFristenrechnerService(rules, holidays),
 			EventDeadline:  services.NewEventDeadlineService(pool, services.NewDeadlineCalculator(holidays), holidays),
+			EventType:      eventTypeSvc,
 			Dashboard:      services.NewDashboardService(pool, users),
 			Note:           services.NewNoteService(pool, projectSvc, appointmentSvc),
 			ChecklistInst:  services.NewChecklistInstanceService(pool, projectSvc),
 			Mail:           mailSvc,
 			Invite:         inviteSvc,
-			Agenda:         services.NewAgendaService(pool, users),
+			Agenda:         services.NewAgendaService(pool, users, eventTypeSvc),
 			Audit:          services.NewAuditService(pool),
 			EmailTemplate:  emailTemplateSvc,
 			Link:           services.NewLinkService(pool),