Fix production build minification error causing blank page

Fixed the "Identifier 'xL' has already been declared" error that occurred
in production builds by switching from SWC minifier to Terser.

Changes:
- Updated vite.config.ts to explicitly use Terser minifier
- Added terser as dev dependency
- Configured safe Terser options to prevent variable name conflicts
- Disabled unsafe optimizations that can cause identifier collisions

This resolves the blank page issue in production while maintaining
bundle size optimization.

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

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

package.json

@@ -98,6 +98,7 @@
     "lovable-tagger": "^1.1.13",
     "postcss": "^8.5.6",
     "tailwindcss": "^3.4.17",
+    "terser": "^5.44.1",
     "typescript": "^5.8.3",
     "typescript-eslint": "^8.38.0",
     "vite": "^5.4.19"