ci: commit workspace changes from notebook and backend fixes (excludes test_env, Frontend)

.env.example

@@ -0,0 +1,20 @@
+# Environment configuration example
+# Copy this file to .env and adjust values
+
+# Application
+ENV=development
+LOG_LEVEL=DEBUG
+
+# Server
+HOST=0.0.0.0
+PORT=8001
+
+# CORS (comma-separated list)
+# CORS_ORIGINS=http://localhost:3000,http://localhost:8000
+
+# Cache
+CACHE_TTL_SECONDS=3600
+CACHE_MAX_SIZE=10000
+
+# Rate limiting
+RATE_LIMIT_PER_MINUTE=100