Fix: Add .env to .gitignore and remove from Git

.gitignore

@@ -1,8 +1,5 @@
+# Dependencies
 **/node_modules
-.next
-.cache
-.build
-*.nfs*
 **/.yarn/
 !**/.yarn/patches
 !**/.yarn/plugins
@@ -12,13 +9,33 @@
 !**/.yarn/cache
 **/.yarn/build-state.yml
 **/.yarn/install-state.gz
+
+# Next.js
+.next
+.cache
+.build
 dist
 target
 out
+*.tsbuildinfo
+
+# Environment variables (CRITICAL - never commit!)
+.env
+.env.local
+.env.production
+.env.*.local
+
+# Docker generated files
+docker-compose.simple.yml
+
+# Logs
 .deploy
 .logs
-*.tsbuildinfo
+*.nfs*
 npm-debug.log*
 yarn-debug.log*
 yarn-error.log*
-.env
+
+# OS files
+.DS_Store
+Thumbs.db