🔧 Fix authentication and document upload issues

## What was done:
✅ Fixed Firebase Admin initialization to use default credentials for Firebase Functions
✅ Updated frontend to use correct Firebase Functions URL (was using Cloud Run URL)
✅ Added comprehensive debugging to authentication middleware
✅ Added debugging to file upload middleware and CORS handling
✅ Added debug buttons to frontend for troubleshooting authentication
✅ Enhanced error handling and logging throughout the stack

## Current issues:
❌ Document upload still returns 400 Bad Request despite authentication working
❌ GET requests work fine (200 OK) but POST upload requests fail
❌ Frontend authentication is working correctly (valid JWT tokens)
❌ Backend authentication middleware is working (rejects invalid tokens)
❌ CORS is configured correctly and allowing requests

## Root cause analysis:
- Authentication is NOT the issue (tokens are valid, GET requests work)
- The problem appears to be in the file upload handling or multer configuration
- Request reaches the server but fails during upload processing
- Need to identify exactly where in the upload pipeline the failure occurs

## TODO next steps:
1. 🔍 Check Firebase Functions logs after next upload attempt to see debugging output
2. 🔍 Verify if request reaches upload middleware (look for '�� Upload middleware called' logs)
3. 🔍 Check if file validation is triggered (look for '🔍 File filter called' logs)
4. 🔍 Identify specific error in upload pipeline (multer, file processing, etc.)
5. 🔍 Test with smaller file or different file type to isolate issue
6. 🔍 Check if issue is with Firebase Functions file size limits or timeout
7. 🔍 Verify multer configuration and file handling in Firebase Functions environment

## Technical details:
- Frontend: https://cim-summarizer.web.app
- Backend: https://us-central1-cim-summarizer.cloudfunctions.net/api
- Authentication: Firebase Auth with JWT tokens (working correctly)
- File upload: Multer with memory storage for immediate GCS upload
- Debug buttons available in production frontend for troubleshooting

backend/.env.example

@@ -1,47 +1,43 @@
-# Backend Environment Variables
+# Backend Environment Variables - Cloud-Only Configuration
 
-# Server Configuration
-PORT=5000
+# App Configuration
 NODE_ENV=development
+PORT=5000
 
-# Database Configuration
-DATABASE_URL=postgresql://username:password@localhost:5432/cim_processor
-DB_HOST=localhost
-DB_PORT=5432
-DB_NAME=cim_processor
-DB_USER=username
-DB_PASSWORD=password
+# Supabase Configuration (Required)
+SUPABASE_URL=your-supabase-project-url
+SUPABASE_ANON_KEY=your-supabase-anon-key
+SUPABASE_SERVICE_KEY=your-supabase-service-key
 
-# Redis Configuration
-REDIS_URL=redis://localhost:6379
-REDIS_HOST=localhost
-REDIS_PORT=6379
-
-# JWT Configuration
-JWT_SECRET=your-super-secret-jwt-key-change-this-in-production
-JWT_EXPIRES_IN=1h
-JWT_REFRESH_SECRET=your-super-secret-refresh-key-change-this-in-production
-JWT_REFRESH_EXPIRES_IN=7d
-
-# File Upload Configuration
-MAX_FILE_SIZE=104857600
-UPLOAD_DIR=uploads
-ALLOWED_FILE_TYPES=application/pdf
+# Vector Database Configuration
+VECTOR_PROVIDER=supabase
 
 # LLM Configuration
-LLM_PROVIDER=openai
-OPENAI_API_KEY=your-openai-api-key
+LLM_PROVIDER=anthropic
 ANTHROPIC_API_KEY=your-anthropic-api-key
-LLM_MODEL=gpt-4
+OPENAI_API_KEY=your-openai-api-key
+LLM_MODEL=claude-3-5-sonnet-20241022
 LLM_MAX_TOKENS=4000
 LLM_TEMPERATURE=0.1
 
-# Storage Configuration
-STORAGE_TYPE=local
-AWS_ACCESS_KEY_ID=your-aws-access-key
-AWS_SECRET_ACCESS_KEY=your-aws-secret-key
-AWS_REGION=us-east-1
-AWS_S3_BUCKET=cim-processor-files
+# JWT Configuration (for compatibility)
+JWT_SECRET=your-super-secret-jwt-key-change-this-in-production
+JWT_REFRESH_SECRET=your-super-secret-refresh-key-change-this-in-production
+
+# Google Cloud Document AI Configuration
+GCLOUD_PROJECT_ID=your-gcloud-project-id
+DOCUMENT_AI_LOCATION=us
+DOCUMENT_AI_PROCESSOR_ID=your-processor-id
+GCS_BUCKET_NAME=your-gcs-bucket-name
+DOCUMENT_AI_OUTPUT_BUCKET_NAME=your-document-ai-output-bucket
+GOOGLE_APPLICATION_CREDENTIALS=./serviceAccountKey.json
+
+# Processing Strategy
+PROCESSING_STRATEGY=document_ai_genkit
+
+# File Upload Configuration
+MAX_FILE_SIZE=104857600
+ALLOWED_FILE_TYPES=application/pdf
 
 # Security Configuration
 BCRYPT_ROUNDS=12
@@ -50,4 +46,30 @@ RATE_LIMIT_MAX_REQUESTS=100
 
 # Logging Configuration
 LOG_LEVEL=info
-LOG_FILE=logs/app.log
+LOG_FILE=logs/app.log
+
+# Agentic RAG Configuration
+AGENTIC_RAG_ENABLED=true
+AGENTIC_RAG_MAX_AGENTS=6
+AGENTIC_RAG_PARALLEL_PROCESSING=true
+AGENTIC_RAG_VALIDATION_STRICT=true
+AGENTIC_RAG_RETRY_ATTEMPTS=3
+AGENTIC_RAG_TIMEOUT_PER_AGENT=60000
+
+# Agent Configuration
+AGENT_DOCUMENT_UNDERSTANDING_ENABLED=true
+AGENT_FINANCIAL_ANALYSIS_ENABLED=true
+AGENT_MARKET_ANALYSIS_ENABLED=true
+AGENT_INVESTMENT_THESIS_ENABLED=true
+AGENT_SYNTHESIS_ENABLED=true
+AGENT_VALIDATION_ENABLED=true
+
+# Quality Control
+AGENTIC_RAG_QUALITY_THRESHOLD=0.8
+AGENTIC_RAG_COMPLETENESS_THRESHOLD=0.9
+AGENTIC_RAG_CONSISTENCY_CHECK=true
+
+# Monitoring and Logging
+AGENTIC_RAG_DETAILED_LOGGING=true
+AGENTIC_RAG_PERFORMANCE_TRACKING=true
+AGENTIC_RAG_ERROR_REPORTING=true