feat(gateway): MosaicPlugin lifecycle + ReloadService + hot reload (P8-013) (#182)

Co-authored-by: Jason Woltje <jason@diversecanvas.com>
Co-committed-by: Jason Woltje <jason@diversecanvas.com>

apps/gateway/src/commands/command-executor.service.ts

@@ -1,11 +1,13 @@
-import { Inject, Injectable, Logger } from '@nestjs/common';
+import { forwardRef, Inject, Injectable, Logger, Optional } from '@nestjs/common';
 import type { QueueHandle } from '@mosaic/queue';
 import type { SlashCommandPayload, SlashCommandResultPayload } from '@mosaic/types';
 import { AgentService } from '../agent/agent.service.js';
-import { CommandRegistryService } from './command-registry.service.js';
-import { SystemOverrideService } from '../preferences/system-override.service.js';
+import { ChatGateway } from '../chat/chat.gateway.js';
 import { SessionGCService } from '../gc/session-gc.service.js';
+import { SystemOverrideService } from '../preferences/system-override.service.js';
+import { ReloadService } from '../reload/reload.service.js';
 import { COMMANDS_REDIS } from './commands.tokens.js';
+import { CommandRegistryService } from './command-registry.service.js';
 
 @Injectable()
 export class CommandExecutorService {
@@ -17,6 +19,12 @@ export class CommandExecutorService {
     @Inject(SystemOverrideService) private readonly systemOverride: SystemOverrideService,
     @Inject(SessionGCService) private readonly sessionGC: SessionGCService,
     @Inject(COMMANDS_REDIS) private readonly redis: QueueHandle['redis'],
+    @Optional()
+    @Inject(forwardRef(() => ReloadService))
+    private readonly reloadService: ReloadService | null,
+    @Optional()
+    @Inject(forwardRef(() => ChatGateway))
+    private readonly chatGateway: ChatGateway | null,
   ) {}
 
   async execute(payload: SlashCommandPayload, userId: string): Promise<SlashCommandResultPayload> {
@@ -94,6 +102,24 @@ export class CommandExecutorService {
           };
         case 'tools':
           return await this.handleTools(conversationId, userId);
+        case 'reload': {
+          if (!this.reloadService) {
+            return {
+              command: 'reload',
+              conversationId,
+              success: false,
+              message: 'ReloadService is not available.',
+            };
+          }
+          const reloadResult = await this.reloadService.reload('command');
+          this.chatGateway?.broadcastReload(reloadResult);
+          return {
+            command: 'reload',
+            success: true,
+            message: reloadResult.message,
+            conversationId,
+          };
+        }
         default:
           return {
             command,