feat: Migrate to ultrathin monolith architecture

Consolidate 3 separate applications (reports-app, data-entry-app, telegram-bot) into a unified
architecture with single backend and frontend:

Backend Changes:
- Unified FastAPI backend at backend/ with modular structure
- Modules: reports, data_entry, telegram in backend/modules/
- Centralized config.py and main.py with all routers registered
- Single worker mode (--workers 1) for Telegram bot compatibility
- Shared Oracle connection pool and JWT authentication
- Unified requirements.txt and environment configuration

Frontend Changes:
- Single Vue.js SPA with module-based routing
- Unified frontend at src/ with modules in src/modules/{reports,data-entry}/
- Shared components and stores in src/shared/
- Error boundaries for module isolation
- Dual API proxy in Vite for module communication

Infrastructure:
- New unified startup scripts: start-prod.sh, start-test.sh, start-backend.sh
- Environment templates: .env.dev.example, .env.test.example, .env.prod.example
- Updated deployment scripts for Windows IIS
- Simplified SSH tunnel management

Documentation:
- Comprehensive CLAUDE.md with architecture overview
- Module-specific docs in docs/{data-entry,telegram}/
- Architecture decision records in docs/ARCHITECTURE-DECISIONS.md
- Deployment guides consolidated in deployment/windows/docs/

This migration reduces complexity, improves maintainability, and enables easier
deployment while maintaining all existing functionality.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

backend/modules/data_entry/routers/__init__.py

@@ -0,0 +1,30 @@
+"""Data Entry module router factory."""
+
+from fastapi import APIRouter
+
+
+def create_data_entry_router() -> APIRouter:
+    """
+    Create and configure Data Entry module router.
+
+    Includes all data entry endpoints:
+    - /receipts - Receipt CRUD and workflow
+    - /ocr - OCR processing for receipts
+    - /nomenclature - Nomenclature syncing from Oracle
+
+    Returns:
+        APIRouter: Configured router for data entry module
+    """
+    router = APIRouter()
+
+    # Import routers here to avoid circular imports
+    from .receipts import router as receipts_router
+    from .ocr import router as ocr_router
+    from .nomenclature import router as nomenclature_router
+
+    # Include all sub-routers (no prefix - already prefixed in main.py with /api/data-entry)
+    router.include_router(receipts_router, prefix="/receipts", tags=["data-entry-receipts"])
+    router.include_router(ocr_router, prefix="/ocr", tags=["data-entry-ocr"])
+    router.include_router(nomenclature_router, prefix="/nomenclature", tags=["data-entry-nomenclature"])
+
+    return router