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/app.module.ts

@@ -23,6 +23,7 @@ import { AssessmentGroupsModule } from './modules/assessment-groups/assessment-g
 import { ProjectsModule } from './modules/projects/projects.module';
 import { MonthlyActualsModule } from './modules/monthly-actuals/monthly-actuals.module';
 import { AttachmentsModule } from './modules/attachments/attachments.module';
+import { InvestmentPlanningModule } from './modules/investment-planning/investment-planning.module';
 
 @Module({
   imports: [
@@ -60,6 +61,7 @@ import { AttachmentsModule } from './modules/attachments/attachments.module';
     ProjectsModule,
     MonthlyActualsModule,
     AttachmentsModule,
+    InvestmentPlanningModule,
   ],
   controllers: [AppController],
 })