fix: add missing @Inject() decorators and fix coord workspace root detection

- Add @Inject() to all gateway constructor params (required without emitDecoratorMetadata)
  - AgentService: ProviderService, CoordService
  - RoutingService: ProviderService
  - ProvidersController: ProviderService, RoutingService
  - SessionsController: AgentService
- Fix coord controller ALLOWED_ROOTS to walk up to monorepo root (pnpm-workspace.yaml)
- Gateway now boots and serves all routes correctly

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

apps/gateway/src/agent/agent.service.ts

@@ -40,9 +40,9 @@ export class AgentService implements OnModuleDestroy {
   private readonly customTools: ToolDefinition[];
 
   constructor(
-    private readonly providerService: ProviderService,
+    @Inject(ProviderService) private readonly providerService: ProviderService,
     @Inject(BRAIN) private readonly brain: Brain,
-    private readonly coordService: CoordService,
+    @Inject(CoordService) private readonly coordService: CoordService,
   ) {
     this.customTools = [...createBrainTools(brain), ...createCoordTools(coordService)];
     this.logger.log(`Registered ${this.customTools.length} custom tools`);