Remove JS obfuscator that broke Mapbox GL map rendering

vite-plugin-obfuscator processes ALL output chunks including vendor
libraries, corrupting Mapbox GL's WebGL shader string literals via
base64 encoding and string splitting. This caused the map to render
as a blank screen in production.

Vite's built-in esbuild minification already mangles identifiers and
removes whitespace, providing sufficient code protection.

Adds regression tests to prevent re-introducing obfuscation plugins.

frontend/tsconfig.node.json

@@ -22,7 +22,6 @@
     // "noUncheckedSideEffectImports": true
   },
   "include": [
-    "vite.config.ts",
-    "vite-plugin-obfuscator.d.ts"
+    "vite.config.ts"
   ]
 }