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/vite.config.ts

@@ -3,26 +3,12 @@ import react from '@vitejs/plugin-react-swc';
 import path from "path";
 import { env } from "process";
 import { defineConfig } from 'vite';
-import { viteObfuscateFile } from 'vite-plugin-obfuscator';
 
 // https://vite.dev/config/
 export default defineConfig({
   plugins: [
     react(),
     tailwindcss(),
-    viteObfuscateFile({
-      compact: true,
-      controlFlowFlattening: false,
-      deadCodeInjection: false,
-      debugProtection: false,
-      identifierNamesGenerator: 'hexadecimal',
-      renameGlobals: false,
-      stringArray: true,
-      stringArrayThreshold: 0.75,
-      stringArrayEncoding: ['base64'],
-      splitStrings: true,
-      splitStringsChunkLength: 10,
-    }),
   ],
   build: {
     outDir: "dist",