feat: member portal Sprint 9 — Ask AI (RAG over message archive)

- AskAIQuery model + migration (logs question/answer/citations per member)
- AskAIService: RAG pipeline — retrieve via tenant-isolated SearchService (Meili),
  ground LLM in top-8 snippets with inline [n] citations, degrade gracefully when
  OPENROUTER_API_KEY absent or no context (snippet fallback)
- Shared api/common/llm-client.ts (mirrors worker's OpenRouter client)
- SearchModule now exports SearchService
- Member endpoints: GET/POST /my/ask (history + ask)
- /my/ask page + AskChat client component: question box, answer cards with sources
- Ask AI nav item (top of member nav)

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

apps/api/src/modules/ask-ai/ask-ai.module.ts

@@ -0,0 +1,10 @@
+import { Module } from '@nestjs/common';
+import { AskAIService } from './ask-ai.service';
+import { SearchModule } from '../search/search.module';
+
+@Module({
+  imports: [SearchModule],
+  providers: [AskAIService],
+  exports: [AskAIService],
+})
+export class AskAIModule {}