Fix code quality violations and exclude Manifest from checks

Document application modes (development/debug/production)
Add global file drop handler, order column normalization, SPA hash fix
Serve CDN assets via /_vendor/ URLs instead of merging into bundles
Add production minification with license preservation
Improve JSON formatting for debugging and production optimization
Add CDN asset caching with CSS URL inlining for production builds
Add three-mode system (development, debug, production)
Update Manifest CLAUDE.md to reflect helper class architecture
Refactor Manifest.php into helper classes for better organization
Pre-manifest-refactor checkpoint: Add app_mode documentation

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

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

config/rsx.php

@@ -89,6 +89,24 @@
  */
 
 return [
+    /*
+    |--------------------------------------------------------------------------
+    | Application Mode
+    |--------------------------------------------------------------------------
+    |
+    | RSX_MODE is the authoritative source of truth for application mode.
+    | Valid values: development, debug, production
+    |
+    | - development: Auto-rebuild, full debugging, sourcemaps
+    | - debug: Production optimizations with sourcemaps for debugging
+    | - production: Full optimization, minification, merging, CDN bundling
+    |
+    | See: php artisan rsx:man app_mode
+    |
+    */
+
+    'mode' => env('RSX_MODE', 'development'),
+
     /*
     |--------------------------------------------------------------------------
     | Manifest Modules
@@ -299,6 +317,18 @@ return [
             '.gitattributes', // Git attributes config
             '._rsx_helper.php', // IDE helper stubs (auto-generated)
         ],
+
+        // Directories to exclude from code quality checks (relative path segments)
+        // These are matched via str_contains, so 'Core/Manifest' matches 'app/RSpade/Core/Manifest/'
+        'excluded_dirs' => [
+            'vendor',
+            'node_modules',
+            'storage',
+            '.git',
+            'public',
+            'resource',
+            'Core/Manifest',  // Manifest builder uses reflection - can't use Manifest API
+        ],
     ],
 
     /*