chore: add .gitignore for React frontend project

.gitignore

@@ -1,10 +1,45 @@
-node_modules
+# Dependencies
+node_modules/
+/.pnp
+.pnp.js
 
+# Build outputs
+/dist
+/build
+*.local
+
+# Environment files (never commit secrets)
 .env
-# Build output
-dist/
+.env.local
+.env.*.local
+.env.bak
 
-# Lock files - clean install
-package-lock.json
-*.bak
-*.bak
+# IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+
+# OS files
+.DS_Store
+Thumbs.db
+
+# Logs
+*.log
+logs/
+
+# Coverage
+coverage/
+.nyc_output/
+
+# TypeScript
+*.tsbuildinfo
+
+# Docker
+docker-compose.override.yml
+
+# Misc
+.cache/
+.tmp/
+*.tmp