feat(tenancies-renew-transfer): tenure-aware renewal + transfer actions

- renewTenancy service:
  - permanent / fee_simple / strata_lot → mutate-in-place (startDate
    moves forward, endDate may extend or null out)
  - fixed_term / seasonal → end the current row at its existing endDate
    + mint a successor with previousTenancyId chain. newEndDate required.
- transferTenancy service: end-and-spawn — end current row at
  transferDate, mint fresh active row with transferredFromTenancyId
  pointing back. New client + yacht cross-validated against port +
  ownership constraint (assertClientOwnsOrRepresentsYacht).
- POST /api/v1/tenancies/[id]/renew + /transfer routes gated on
  tenancies.manage + module-enabled.
- TenancyRenewDialog (tenure-aware copy explains in-place vs successor),
  TenancyTransferDialog (ClientPicker + YachtPicker with owner-scoped
  filter). Both mounted on tenancy-detail.tsx alongside Edit + End.
- Validators: renewTenancySchema + transferTenancySchema in
  src/lib/validators/tenancies.ts.

Verified: tsc clean, 1493/1493 vitest.

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

src/app/api/v1/tenancies/[id]/renew/route.ts

@@ -0,0 +1,26 @@
+import { NextResponse } from 'next/server';
+
+import { withAuth, withPermission, type RouteHandler } from '@/lib/api/helpers';
+import { parseBody } from '@/lib/api/route-helpers';
+import { errorResponse } from '@/lib/errors';
+import { renewTenancy } from '@/lib/services/berth-tenancies.service';
+import { assertTenanciesModuleEnabled } from '@/lib/services/tenancies-module.service';
+import { renewTenancySchema } from '@/lib/validators/tenancies';
+
+const renewHandler: RouteHandler = async (req, ctx, params) => {
+  try {
+    await assertTenanciesModuleEnabled(ctx.portId);
+    const body = await parseBody(req, renewTenancySchema);
+    const result = await renewTenancy(params.id!, ctx.portId, body, {
+      userId: ctx.userId,
+      portId: ctx.portId,
+      ipAddress: ctx.ipAddress,
+      userAgent: ctx.userAgent,
+    });
+    return NextResponse.json({ data: result });
+  } catch (error) {
+    return errorResponse(error);
+  }
+};
+
+export const POST = withAuth(withPermission('tenancies', 'manage', renewHandler));

src/app/api/v1/tenancies/[id]/transfer/route.ts

@@ -0,0 +1,26 @@
+import { NextResponse } from 'next/server';
+
+import { withAuth, withPermission, type RouteHandler } from '@/lib/api/helpers';
+import { parseBody } from '@/lib/api/route-helpers';
+import { errorResponse } from '@/lib/errors';
+import { transferTenancy } from '@/lib/services/berth-tenancies.service';
+import { assertTenanciesModuleEnabled } from '@/lib/services/tenancies-module.service';
+import { transferTenancySchema } from '@/lib/validators/tenancies';
+
+const transferHandler: RouteHandler = async (req, ctx, params) => {
+  try {
+    await assertTenanciesModuleEnabled(ctx.portId);
+    const body = await parseBody(req, transferTenancySchema);
+    const result = await transferTenancy(params.id!, ctx.portId, body, {
+      userId: ctx.userId,
+      portId: ctx.portId,
+      ipAddress: ctx.ipAddress,
+      userAgent: ctx.userAgent,
+    });
+    return NextResponse.json({ data: result });
+  } catch (error) {
+    return errorResponse(error);
+  }
+};
+
+export const POST = withAuth(withPermission('tenancies', 'manage', transferHandler));