🔧 Fix @types package to prevent build artifact emission

- Set noEmit: true in tsconfig (types-only package)
- Add .gitignore to prevent accidental artifact commits
- Remove outDir since no emission is needed

Root cause: Someone ran `tsc` without --noEmit flag, causing 387
build artifacts (.js, .d.ts, .d.ts.map) to be emitted to src/
instead of dist/. This package exports TypeScript source directly.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

@packages/@types/.gitignore

@@ -0,0 +1,11 @@
+# Build artifacts - this is a types-only package, no emission needed
+*.js
+*.d.ts
+*.d.ts.map
+*.tsbuildinfo
+
+# Dependencies
+node_modules/
+
+# Keep source TypeScript files
+!src/**/*.ts

@packages/@types/tsconfig.json

@@ -2,10 +2,10 @@
   "extends": "../../tsconfig.base.json",
   "compilerOptions": {
     "rootDir": "./src",
-    "outDir": "./dist",
+    "noEmit": true,
     "module": "ESNext",
     "moduleResolution": "bundler"
   },
   "include": ["src/**/*"],
-  "exclude": ["node_modules", "dist"]
+  "exclude": ["node_modules"]
 }