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/Plugin.php

@@ -0,0 +1,150 @@
+<?php
+/**
+ * Main plugin class.
+ *
+ * @package WP_Prometheus
+ */
+
+namespace Magdev\WpPrometheus;
+
+use Magdev\WpPrometheus\Admin\Settings;
+use Magdev\WpPrometheus\Endpoint\MetricsEndpoint;
+use Magdev\WpPrometheus\License\Manager as LicenseManager;
+use Magdev\WpPrometheus\Metrics\Collector;
+
+// Prevent direct file access.
+if ( ! defined( 'ABSPATH' ) ) {
+    exit;
+}
+
+/**
+ * Plugin singleton class.
+ *
+ * Initializes and manages all plugin components.
+ */
+final class Plugin {
+
+    /**
+     * Singleton instance.
+     *
+     * @var Plugin|null
+     */
+    private static ?Plugin $instance = null;
+
+    /**
+     * Metrics collector instance.
+     *
+     * @var Collector|null
+     */
+    private ?Collector $collector = null;
+
+    /**
+     * Get singleton instance.
+     *
+     * @return Plugin
+     */
+    public static function get_instance(): Plugin {
+        if ( null === self::$instance ) {
+            self::$instance = new self();
+        }
+        return self::$instance;
+    }
+
+    /**
+     * Private constructor to enforce singleton pattern.
+     */
+    private function __construct() {
+        $this->init_components();
+        $this->init_hooks();
+        $this->load_textdomain();
+    }
+
+    /**
+     * Prevent cloning.
+     *
+     * @return void
+     */
+    private function __clone() {}
+
+    /**
+     * Prevent unserialization.
+     *
+     * @throws \Exception Always throws to prevent unserialization.
+     * @return void
+     */
+    public function __wakeup(): void {
+        throw new \Exception( 'Cannot unserialize singleton' );
+    }
+
+    /**
+     * Initialize plugin components.
+     *
+     * @return void
+     */
+    private function init_components(): void {
+        // Initialize license manager.
+        LicenseManager::get_instance();
+
+        // Initialize admin settings (always needed).
+        if ( is_admin() ) {
+            new Settings();
+        }
+
+        // Initialize metrics endpoint (only if licensed).
+        if ( LicenseManager::is_license_valid() ) {
+            $this->collector = new Collector();
+            new MetricsEndpoint( $this->collector );
+        }
+    }
+
+    /**
+     * Initialize WordPress hooks.
+     *
+     * @return void
+     */
+    private function init_hooks(): void {
+        // Add settings link to plugins page.
+        add_filter( 'plugin_action_links_' . WP_PROMETHEUS_BASENAME, array( $this, 'add_plugin_action_links' ) );
+    }
+
+    /**
+     * Add action links to the plugins page.
+     *
+     * @param array $links Existing action links.
+     * @return array Modified action links.
+     */
+    public function add_plugin_action_links( array $links ): array {
+        $settings_link = sprintf(
+            '<a href="%s">%s</a>',
+            esc_url( admin_url( 'options-general.php?page=wp-prometheus' ) ),
+            esc_html__( 'Settings', 'wp-prometheus' )
+        );
+
+        // Add our link at the beginning.
+        array_unshift( $links, $settings_link );
+
+        return $links;
+    }
+
+    /**
+     * Load plugin textdomain.
+     *
+     * @return void
+     */
+    private function load_textdomain(): void {
+        load_plugin_textdomain(
+            'wp-prometheus',
+            false,
+            dirname( WP_PROMETHEUS_BASENAME ) . '/languages'
+        );
+    }
+
+    /**
+     * Get the metrics collector.
+     *
+     * @return Collector|null
+     */
+    public function get_collector(): ?Collector {
+        return $this->collector;
+    }
+}