Migrate JavaScript to TypeScript with full type safety

- Rename all .js/.jsx files to .ts/.tsx across resources/js and theme dirs
- Add TypeScript 6.0 with strict mode, tsconfig.json
- Add type definitions for Inertia page props, Alpine.js, Turbolinks
- Update vite.config.js entries to .ts/.tsx extensions
- Update all Blade @vite() calls to match new .ts/.tsx entry points
- Add TypeScript ESLint config (replacing unused Vue plugin)
- Add @types/react, @types/react-dom, @types/lodash
- Add typecheck script and integrate into check pipeline
- Full tsc --noEmit, ESLint, and production build pass cleanly

resources/themes/atom/js/bootstrap.ts

@@ -0,0 +1,7 @@
+import axios from "axios";
+import Turbolinks from "turbolinks";
+
+window.axios = axios;
+window.axios.defaults.headers.common["X-Requested-With"] = "XMLHttpRequest";
+
+Turbolinks.start();