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>

src/Installer.php

@@ -0,0 +1,103 @@
+<?php
+/**
+ * Plugin installer class.
+ *
+ * @package WP_Prometheus
+ */
+
+namespace Magdev\WpPrometheus;
+
+// Prevent direct file access.
+if ( ! defined( 'ABSPATH' ) ) {
+    exit;
+}
+
+/**
+ * Installer class.
+ *
+ * Handles plugin activation, deactivation, and uninstallation.
+ */
+final class Installer {
+
+    /**
+     * Plugin activation.
+     *
+     * @return void
+     */
+    public static function activate(): void {
+        // Set default options.
+        self::set_default_options();
+
+        // Flush rewrite rules for the metrics endpoint.
+        flush_rewrite_rules();
+
+        // Store activation time for reference.
+        update_option( 'wp_prometheus_activated', time() );
+    }
+
+    /**
+     * Plugin deactivation.
+     *
+     * @return void
+     */
+    public static function deactivate(): void {
+        // Flush rewrite rules.
+        flush_rewrite_rules();
+    }
+
+    /**
+     * Plugin uninstallation.
+     *
+     * @return void
+     */
+    public static function uninstall(): void {
+        // Remove all plugin options.
+        $options = array(
+            'wp_prometheus_activated',
+            'wp_prometheus_license_key',
+            'wp_prometheus_license_server_url',
+            'wp_prometheus_license_server_secret',
+            'wp_prometheus_license_status',
+            'wp_prometheus_license_data',
+            'wp_prometheus_license_last_check',
+            'wp_prometheus_auth_token',
+            'wp_prometheus_enable_default_metrics',
+            'wp_prometheus_enabled_metrics',
+        );
+
+        foreach ( $options as $option ) {
+            delete_option( $option );
+        }
+
+        // Remove transients.
+        delete_transient( 'wp_prometheus_license_check' );
+    }
+
+    /**
+     * Set default plugin options.
+     *
+     * @return void
+     */
+    private static function set_default_options(): void {
+        // Generate a random auth token if not set.
+        if ( ! get_option( 'wp_prometheus_auth_token' ) ) {
+            update_option( 'wp_prometheus_auth_token', wp_generate_password( 32, false ) );
+        }
+
+        // Enable default metrics by default.
+        if ( false === get_option( 'wp_prometheus_enable_default_metrics' ) ) {
+            update_option( 'wp_prometheus_enable_default_metrics', 1 );
+        }
+
+        // Default enabled metrics.
+        if ( false === get_option( 'wp_prometheus_enabled_metrics' ) ) {
+            update_option( 'wp_prometheus_enabled_metrics', array(
+                'wordpress_info',
+                'wordpress_users_total',
+                'wordpress_posts_total',
+                'wordpress_comments_total',
+                'wordpress_plugins_total',
+            ) );
+        }
+    }
+}