Initial plugin setup (v0.0.1)

- Create initial WordPress plugin structure
- Add Prometheus metrics collector with default metrics
- Implement authenticated /metrics endpoint with Bearer token
- Add license management integration
- Create admin settings page under Settings > Metrics
- Set up Gitea CI/CD pipeline for automated releases
- Add extensibility via wp_prometheus_collect_metrics hook

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

uninstall.php

@@ -0,0 +1,18 @@
+<?php
+/**
+ * Uninstall WP Prometheus plugin.
+ *
+ * @package WP_Prometheus
+ */
+
+// If uninstall.php is not called by WordPress, die.
+if ( ! defined( 'WP_UNINSTALL_PLUGIN' ) ) {
+    die;
+}
+
+// Load the autoloader if it exists.
+$autoloader = __DIR__ . '/vendor/autoload.php';
+if ( file_exists( $autoloader ) ) {
+    require_once $autoloader;
+    \Magdev\WpPrometheus\Installer::uninstall();
+}