Phase 5: AI investment planning - CD rate fetcher and AI recommendation engine

- Add shared.cd_rates table for cross-tenant market data (CD rates from Bankrate)
- Create standalone Puppeteer scraper script (scripts/fetch-cd-rates.ts) for cron-based rate fetching
- Add investment-planning backend module with 3 endpoints: snapshot, cd-rates, recommendations
- AI service gathers tenant financial data (accounts, investments, budgets, projects, cash flow) and calls OpenAI-compatible API (NVIDIA endpoint) for structured investment recommendations
- Create InvestmentPlanningPage with summary cards, current investments table, market CD rates table, and AI recommendation accordion
- Add Investment Planning to sidebar under Planning menu
- Configure AI_API_URL, AI_API_KEY, AI_MODEL environment variables

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

backend/src/modules/investment-planning/investment-planning.module.ts

@@ -0,0 +1,9 @@
+import { Module } from '@nestjs/common';
+import { InvestmentPlanningController } from './investment-planning.controller';
+import { InvestmentPlanningService } from './investment-planning.service';
+
+@Module({
+  controllers: [InvestmentPlanningController],
+  providers: [InvestmentPlanningService],
+})
+export class InvestmentPlanningModule {}