feat(tenancies-p6-followup): generic create dialog + edit dialog + self-FKs

- Migration 0086: berth_tenancies.previous_tenancy_id +
  transferred_from_tenancy_id self-FKs + partial indexes. Per
  docs/tenancies-design.md these chain renewal / transfer successors
  to predecessors for fixed-term and seasonal lineage. Schema mirrored
  in tenancies.ts with AnyPgColumn typed-import.
- POST /api/v1/tenancies (generic create): accepts berthId in the
  body so client + yacht tab entry points don't have to bounce through
  /api/v1/berths/[id]/tenancies. Same createPending service helper.
- TenancyCreateDialog: <TenancyCreateDialog open clientId? yachtId?
  berthId? /> with all three pickers; pre-fills the carrier from the
  parent entity. POSTs to /api/v1/tenancies; "Create" and
  "Create and activate" CTAs both wire to the new endpoint.
- Mounted on ClientTenanciesTab + YachtTenanciesTab behind
  <PermissionGate resource="tenancies" action="manage"> so reps can
  mint tenancies directly from those tabs without bouncing through
  the berth page.
- TenancyEditDialog: edit metadata only (start/end dates, tenure type,
  notes) via the new action='update' branch on the [id] PATCH route.
  Status transitions stay on activate/end/cancel. Wired into the
  tenancy detail page header. Outer wrapper unmounts on close so the
  form re-initialises from current row data without setState-in-effect.
- updateTenancy service helper + PATCH action='update' branch added.
  Audit-logged + emits berth_tenancy:activated to invalidate detail
  query caches.

Renew + Transfer dialogs deferred — both need lineage UX decisions
(tenure-aware mutate-in-place vs new-row spawn; client/yacht swap
semantics) and the self-FK columns this commit lands are the
underpinning. Next sub-task.

Verified: tsc clean, 1493/1493 vitest, migration applied.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/lib/validators/tenancies.ts

@@ -28,6 +28,20 @@ export const cancelSchema = z.object({
   reason: z.string().optional(),
 });
 
+/** PATCH body for the "edit metadata" idiom — touches notes / dates /
+ *  tenure type without crossing a status boundary. Status transitions
+ *  flow through activate / endTenancy / cancel; this is non-transition
+ *  metadata only. */
+export const updateTenancySchema = z
+  .object({
+    startDate: z.coerce.date().optional(),
+    endDate: z.coerce.date().nullable().optional(),
+    tenureType: z.enum(TENURE_TYPES).optional(),
+    notes: z.string().nullable().optional(),
+  })
+  .refine((d) => Object.keys(d).length > 0, { message: 'At least one field must be provided' });
+export type UpdateTenancyInput = z.infer<typeof updateTenancySchema>;
+
 export const listTenanciesSchema = baseListQuerySchema.extend({
   status: z.enum(TENANCY_STATUSES).optional(),
   berthId: z.string().optional(),