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>

node_modules/mdn-data/css/definitions.json

@@ -7,9 +7,11 @@
       "CSS Angles",
       "CSS Animations",
       "CSS Backgrounds and Borders",
+      "CSS Basic User Interface",
       "CSS Box Model",
       "CSS Box Alignment",
       "CSS Break",
+      "CSS Cascading and Inheritance",
       "CSS Charsets",
       "CSS Color",
       "CSS Columns",
@@ -55,8 +57,8 @@
       "CSS Transitions",
       "CSS Types",
       "CSS Units",
-      "CSS Basic User Interface",
       "CSS Variables",
+      "CSS View Transitions",
       "CSS Will Change",
       "CSS Writing Modes",
       "CSSOM View",
@@ -71,6 +73,7 @@
       "Pseudo-classes",
       "Pseudo-elements",
       "Selectors",
+      "Scalable Vector Graphics",
       "WebKit Extensions"
     ]
   }