test(schema): verify partial unique indexes and case-insensitive company uniqueness

Adds integration test covering:
- idx_yoh_active: only one active ownership row per yacht
- idx_br_active: only one active reservation per berth (non-active rows
  are ignored by the partial index)
- Case-insensitive company name uniqueness within a port, with same-name
  companies allowed across different ports

Extends tests/helpers/factories.ts with async DB-inserting factories for
ports, clients, berths, yachts (+ ownership history row) and companies.
The new factories use the app's `db` handle so FK and partial unique
indexes are enforced by Postgres. The in-memory data helpers used by
unit tests (makeAuditMeta, makeCreateClientInput, permission helpers)
are preserved.

tests/integration/schema-constraints.test.ts

@@ -0,0 +1,169 @@
+/**
+ * Schema constraint integration tests.
+ *
+ * Verifies DB-level enforcement of:
+ *  - Partial unique index idx_yoh_active (one active ownership row per yacht)
+ *  - Partial unique index idx_br_active (one active reservation per berth)
+ *  - Non-active reservations on the same berth are permitted
+ *  - Case-insensitive company name uniqueness within a port
+ *  - Same company name allowed across different ports
+ */
+import { describe, it, expect, beforeAll } from 'vitest';
+
+import { db } from '@/lib/db';
+import { yachtOwnershipHistory } from '@/lib/db/schema/yachts';
+import { berthReservations } from '@/lib/db/schema/reservations';
+import { companies } from '@/lib/db/schema/companies';
+import { makeBerth, makeClient, makeCompany, makePort, makeYacht } from '../helpers/factories';
+
+// ─── DB availability ─────────────────────────────────────────────────────────
+
+let dbAvailable = false;
+
+beforeAll(async () => {
+  try {
+    await db.execute(`SELECT 1`);
+    dbAvailable = true;
+  } catch (err) {
+    console.warn(
+      '[schema-constraints] DATABASE_URL not reachable — skipping integration tests',
+      err,
+    );
+  }
+});
+
+function itDb(name: string, fn: () => Promise<void>) {
+  it(name, async () => {
+    if (!dbAvailable) return;
+    await fn();
+  });
+}
+
+// ─── Tests ───────────────────────────────────────────────────────────────────
+
+describe('schema constraints', () => {
+  itDb(
+    'rejects a second active ownership row per yacht (partial unique idx_yoh_active)',
+    async () => {
+      const port = await makePort();
+      const clientA = await makeClient({ portId: port.id });
+      const clientB = await makeClient({ portId: port.id });
+      const yacht = await makeYacht({
+        portId: port.id,
+        ownerType: 'client',
+        ownerId: clientA.id,
+      });
+      // makeYacht already inserted one active (end_date IS NULL) ownership row.
+
+      await expect(
+        db.insert(yachtOwnershipHistory).values({
+          yachtId: yacht.id,
+          ownerType: 'client',
+          ownerId: clientB.id,
+          startDate: new Date(),
+          endDate: null, // another open row — should violate partial unique
+          createdBy: 'test',
+        }),
+      ).rejects.toThrow(/duplicate key|unique/i);
+    },
+  );
+
+  itDb('rejects a second active reservation per berth (partial unique idx_br_active)', async () => {
+    const port = await makePort();
+    const clientA = await makeClient({ portId: port.id });
+    const clientB = await makeClient({ portId: port.id });
+    const yachtA = await makeYacht({
+      portId: port.id,
+      ownerType: 'client',
+      ownerId: clientA.id,
+    });
+    const yachtB = await makeYacht({
+      portId: port.id,
+      ownerType: 'client',
+      ownerId: clientB.id,
+    });
+    const berth = await makeBerth({ portId: port.id });
+
+    await db.insert(berthReservations).values({
+      berthId: berth.id,
+      portId: port.id,
+      clientId: clientA.id,
+      yachtId: yachtA.id,
+      status: 'active',
+      startDate: new Date(),
+      createdBy: 'test',
+    });
+
+    await expect(
+      db.insert(berthReservations).values({
+        berthId: berth.id,
+        portId: port.id,
+        clientId: clientB.id,
+        yachtId: yachtB.id,
+        status: 'active',
+        startDate: new Date(),
+        createdBy: 'test',
+      }),
+    ).rejects.toThrow(/duplicate key|unique/i);
+  });
+
+  itDb(
+    'allows multiple non-active reservations on the same berth (partial index ignores non-active)',
+    async () => {
+      const port = await makePort();
+      const clientA = await makeClient({ portId: port.id });
+      const yachtA = await makeYacht({
+        portId: port.id,
+        ownerType: 'client',
+        ownerId: clientA.id,
+      });
+      const berth = await makeBerth({ portId: port.id });
+
+      // Two ended reservations on same berth — both should succeed
+      // (partial index only constrains status='active').
+      await expect(
+        db.insert(berthReservations).values([
+          {
+            berthId: berth.id,
+            portId: port.id,
+            clientId: clientA.id,
+            yachtId: yachtA.id,
+            status: 'ended',
+            startDate: new Date('2024-01-01'),
+            endDate: new Date('2024-06-30'),
+            createdBy: 'test',
+          },
+          {
+            berthId: berth.id,
+            portId: port.id,
+            clientId: clientA.id,
+            yachtId: yachtA.id,
+            status: 'ended',
+            startDate: new Date('2024-07-01'),
+            endDate: new Date('2024-12-31'),
+            createdBy: 'test',
+          },
+        ]),
+      ).resolves.toBeDefined();
+    },
+  );
+
+  itDb('enforces case-insensitive company name uniqueness per port', async () => {
+    const port = await makePort();
+    await makeCompany({ portId: port.id, overrides: { name: 'Aegean Holdings' } });
+
+    await expect(
+      db.insert(companies).values({ portId: port.id, name: 'AEGEAN HOLDINGS' }),
+    ).rejects.toThrow(/duplicate key|unique/i);
+  });
+
+  itDb('allows same-name companies in different ports', async () => {
+    const portA = await makePort();
+    const portB = await makePort();
+    await makeCompany({ portId: portA.id, overrides: { name: 'Aegean Holdings' } });
+
+    await expect(
+      db.insert(companies).values({ portId: portB.id, name: 'Aegean Holdings' }),
+    ).resolves.toBeDefined();
+  });
+});