fix(db): bootstrap migrations on local-tier gateway startup

Fresh `mosaic gateway install` (npm) left the gateway DB schema empty —
sign-in 500'd with `relation "users" does not exist`, and every entry
point (auth, bootstrap setup) failed because they all query the users
table first. Five stacked bugs on the local (PGlite) tier:

1. `packages/db/package.json` `files: ["dist"]` excluded the `drizzle/`
   SQL migrations from the published tarball.
2. `runMigrations()` only supports postgres-js — unusable for embedded
   PGlite.
3. `apps/gateway/src/database/database.module.ts` never invoked
   migrations at startup.
4. `createPgliteDb` didn't load pgvector, so migration 0001's
   `CREATE EXTENSION vector` failed.
5. Drizzle's PG migrator wraps every migration in one outer
   transaction, which trips Postgres' `check_safe_enum_use` on
   migration 0009 (`ALTER TYPE ADD VALUE 'pending'` → `SET DEFAULT
   'pending'` in the same tx).

Changes:
- Ship `drizzle/` in the published tarball.
- `createPgliteDb` loads `@electric-sql/pglite/vector`.
- New `runPgliteMigrations(handle)` walks the Drizzle journal and
  runs each statement-breakpoint chunk through PGlite's `client.exec()`
  (autocommit per statement). Records into `drizzle.__drizzle_migrations`
  for interop with the postgres-js path. Per-statement try/catch
  surfaces which statement of which migration failed.
- `DatabaseModule` runs migrations in `OnModuleInit` before
  `app.listen()`. Local tier: explicit `runPgliteMigrations` then
  `storageAdapter.migrate()`. Postgres tier: just `storageAdapter.migrate()`,
  which already calls `runMigrations(url)` internally — no double-call.
- Removed `packages/storage/src/test-utils/pglite-with-vector.ts`. The
  "intentionally not exported" rationale is moot now that migration
  0001 forces pgvector load anyway. The integration test uses
  `createPgliteDb` + `runPgliteMigrations` from `@mosaicstack/db`.

Tests: BetterAuth tables exist after migrate; idempotent (re-runs 0009);
partial-failure surfaces statement-level context and leaves no ledger row.

QA on a fresh PGlite install:
- `Applying PGlite schema migrations...` then `Initializing storage
  adapter (pglite)...` in startup log.
- `GET /api/bootstrap/status` → `{"needsSetup":true}` HTTP 200 (was 500).
- `POST /api/bootstrap/setup` reaches Zod validator (was 500).

Scope: this PR fixes the local (PGlite) tier. Postgres-tier first
install still has the outer-transaction problem and a journal ordering
bug (0009's `when` < 0008's). Documented inline as TODO and in the
scratchpad — needs a separate change with real-Postgres validation.

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

packages/db/src/migrate.test.ts

@@ -0,0 +1,70 @@
+import { mkdtempSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { sql } from 'drizzle-orm';
+import { afterEach, beforeEach, describe, expect, it } from 'vitest';
+import { createPgliteDb } from './client-pglite.js';
+import { runPgliteMigrations } from './migrate.js';
+import type { DbHandle } from './client.js';
+
+interface PgliteExec {
+  exec(query: string): Promise<unknown>;
+}
+
+describe('runPgliteMigrations', () => {
+  let dataDir: string;
+  let handle: DbHandle;
+
+  beforeEach(() => {
+    dataDir = mkdtempSync(join(tmpdir(), 'mosaic-db-migrate-test-'));
+    handle = createPgliteDb(dataDir);
+  });
+
+  afterEach(async () => {
+    await handle.close();
+    rmSync(dataDir, { recursive: true, force: true });
+  });
+
+  it('creates the BetterAuth tables required by the gateway', async () => {
+    await runPgliteMigrations(handle);
+
+    const result = (await handle.db.execute(sql`
+      SELECT table_name FROM information_schema.tables
+      WHERE table_schema = 'public'
+      ORDER BY table_name
+    `)) as unknown as { rows: Array<{ table_name: string }> };
+
+    const tables = result.rows.map((r) => r.table_name);
+
+    // Auth tables — required for sign-in / bootstrap to function.
+    expect(tables).toContain('users');
+    expect(tables).toContain('sessions');
+    expect(tables).toContain('accounts');
+    expect(tables).toContain('verifications');
+
+    // Schema sanity check — admin token table consumed by mosaic gateway config.
+    expect(tables).toContain('admin_tokens');
+  });
+
+  it('is idempotent — running twice does not error', async () => {
+    await runPgliteMigrations(handle);
+    await expect(runPgliteMigrations(handle)).resolves.toBeUndefined();
+  });
+
+  it('surfaces statement-level error context on failure and leaves no ledger row', async () => {
+    // Pre-create a `users` table that conflicts with migration 0000's CREATE TABLE,
+    // forcing it to fail without IF NOT EXISTS.
+    const client = (handle.db as unknown as { $client: PgliteExec }).$client;
+    await client.exec('CREATE TABLE users (sentinel text)');
+
+    await expect(runPgliteMigrations(handle)).rejects.toThrow(
+      /migration hash=[a-f0-9]+ statement #\d+ failed/,
+    );
+
+    // Ledger should be empty — partial application must not pretend to be complete.
+    const ledger = (await handle.db.execute(
+      sql`SELECT count(*)::int AS count FROM drizzle.__drizzle_migrations`,
+    )) as unknown as { rows: Array<{ count: number }> };
+    expect(ledger.rows[0]?.count).toBe(0);
+  });
+});