feat(gateway): WorkspaceService + ProjectBootstrapService + TeamsService (P8-015)

- WorkspaceService: path resolution, git init/clone, directory lifecycle (create/delete/exists), user and team root provisioning
- ProjectBootstrapService: orchestrates DB record creation (via Brain) + workspace directory init in a single call
- TeamsService: isMember, canAccessProject, findAll, findById, listMembers via Drizzle DB queries
- WorkspaceController: POST /api/workspaces — auth-guarded project bootstrap endpoint
- TeamsController: GET /api/teams, /:teamId, /:teamId/members, /:teamId/members/:userId
- WorkspaceModule wired into AppModule
- workspace.service.spec.ts: 5 unit tests for resolvePath (user, team, fallback, env var, default)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/gateway/src/app.module.ts

@@ -21,6 +21,7 @@ import { CommandsModule } from './commands/commands.module.js';
 import { PreferencesModule } from './preferences/preferences.module.js';
 import { GCModule } from './gc/gc.module.js';
 import { ReloadModule } from './reload/reload.module.js';
+import { WorkspaceModule } from './workspace/workspace.module.js';
 import { ThrottlerGuard, ThrottlerModule } from '@nestjs/throttler';
 
 @Module({
@@ -46,6 +47,7 @@ import { ThrottlerGuard, ThrottlerModule } from '@nestjs/throttler';
     CommandsModule,
     GCModule,
     ReloadModule,
+    WorkspaceModule,
   ],
   controllers: [HealthController],
   providers: [