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/nikic/php-parser/lib/PhpParser/Builder/Use_.php

@@ -0,0 +1,49 @@
+<?php declare(strict_types=1);
+
+namespace PhpParser\Builder;
+
+use PhpParser\Builder;
+use PhpParser\BuilderHelpers;
+use PhpParser\Node;
+use PhpParser\Node\Stmt;
+
+class Use_ implements Builder {
+    protected Node\Name $name;
+    /** @var Stmt\Use_::TYPE_* */
+    protected int $type;
+    protected ?string $alias = null;
+
+    /**
+     * Creates a name use (alias) builder.
+     *
+     * @param Node\Name|string $name Name of the entity (namespace, class, function, constant) to alias
+     * @param Stmt\Use_::TYPE_* $type One of the Stmt\Use_::TYPE_* constants
+     */
+    public function __construct($name, int $type) {
+        $this->name = BuilderHelpers::normalizeName($name);
+        $this->type = $type;
+    }
+
+    /**
+     * Sets alias for used name.
+     *
+     * @param string $alias Alias to use (last component of full name by default)
+     *
+     * @return $this The builder instance (for fluid interface)
+     */
+    public function as(string $alias) {
+        $this->alias = $alias;
+        return $this;
+    }
+
+    /**
+     * Returns the built node.
+     *
+     * @return Stmt\Use_ The built node
+     */
+    public function getNode(): Node {
+        return new Stmt\Use_([
+            new Node\UseItem($this->name, $this->alias)
+        ], $this->type);
+    }
+}