Add .gitignore — exclude saves and build artifacts

.gitignore

@@ -1,24 +1,15 @@
-# Logs
-logs
-*.log
-npm-debug.log*
-yarn-debug.log*
-yarn-error.log*
-pnpm-debug.log*
-lerna-debug.log*
+# Dependencies
+node_modules/
 
-node_modules
-dist
-dist-ssr
-*.local
+# Build output
+dist/
 
-# Editor directories and files
-.vscode/*
-!.vscode/extensions.json
-.idea
-.DS_Store
-*.suo
-*.ntvs*
-*.njsproj
-*.sln
-*.sw?
+# Player save files — never commit
+data/saves/
+
+# PM2 logs
+logs/
+
+# Environment
+.env
+.env.local