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/squizlabs/php_codesniffer/tests/EndToEnd/Fixtures/endtoend.xml.dist

@@ -0,0 +1,13 @@
+<?xml version="1.0"?>
+<ruleset xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" name="EndToEndTests" xsi:noNamespaceSchemaLocation="phpcs.xsd">
+    <description>The coding standard for end to end tests.</description>
+
+    <rule ref="PSR12"/>
+
+    <file>.</file>
+
+    <arg name="basepath" value="."/>
+    <arg name="colors"/>
+    <arg name="parallel" value="75"/>
+    <arg value="p"/>
+</ruleset>