refactor: Cleanup git state - commit all staged changes

Major refactoring cleanup:
- Add new controller architecture (class-controller-*.php)
- Add new settings-v2 UI (views/settings-v2/)
- Add new CSS architecture (agentic-sidebar.css, tokens)
- Add esbuild build pipeline (scripts/build.js, package.json)
- Add composer dependencies (vendor/)
- Add frontend src directory (assets/js/src/index.jsx)
- Add documentation files
- Remove old/obsolete files (class-settings.php, old CSS)

This commits all pending changes from previous refactoring efforts.

vendor/jawira/plantuml/composer.json

@@ -0,0 +1,25 @@
+{
+  "name": "jawira/plantuml",
+  "type": "library",
+  "description": "Provides PlantUML executable and plantuml.jar",
+  "keywords": [
+    "plantuml",
+    "plantuml.jar",
+    "uml",
+    "diagram",
+    "jar"
+  ],
+  "license": "GPL-3.0-or-later",
+  "authors": [
+    {
+      "name": "Jawira Portugal"
+    }
+  ],
+  "config": {
+    "preferred-install": "dist",
+    "sort-packages": true
+  },
+  "bin": [
+    "bin/plantuml"
+  ]
+}