Add queue-based media download system with rate limiting

- Add download_status, retry_after, queued_at columns to mls_media table
- Add mls_media_log table for download attempt tracking
- Rewrite media handler to queue downloads instead of immediate download
- Add 700ms delay between downloads (25% buffer over 2/sec limit)
- Add 3-hour backoff for rate-limited (429) responses
- Add max 5 attempts before marking as permanently failed
- Add wp mls media command: status, process, reset, logs
- Deprecate wp mls sync media in favor of wp mls media process
- Update documentation with queue system details and cron examples

Media downloads are now separate from property sync:
1. wp mls sync full/incremental - syncs properties, queues media
2. wp mls media process - downloads queued media with rate limiting

Generated with [Claude Code](https://claude.com/claude-code)

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

wp-content/plugins/mls-by-hansonxyz/includes/class-mls-db.php

@@ -55,6 +55,13 @@ class MLS_DB {
         return $this->get_table_name(MLS_TABLE_SYNC_LOG);
     }
 
+    /**
+     * Get media log table name
+     */
+    public function media_log_table() {
+        return $this->get_table_name(MLS_TABLE_MEDIA_LOG);
+    }
+
     /**
      * Create all database tables
      */
@@ -163,6 +170,9 @@ class MLS_DB {
             downloaded_at DATETIME DEFAULT NULL,
             download_attempts INT(3) DEFAULT 0,
             download_error TEXT DEFAULT NULL,
+            retry_after DATETIME DEFAULT NULL,
+            queued_at DATETIME DEFAULT NULL,
+            download_status VARCHAR(20) DEFAULT 'pending',
 
             created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
             updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
@@ -170,7 +180,10 @@ class MLS_DB {
             PRIMARY KEY (id),
             UNIQUE KEY listing_media (listing_key, media_key),
             KEY listing_key (listing_key),
-            KEY media_order (media_order)
+            KEY media_order (media_order),
+            KEY download_status (download_status),
+            KEY retry_after (retry_after),
+            KEY queued_at (queued_at)
         ) {$charset_collate};";
 
         dbDelta($sql_media);
@@ -239,6 +252,29 @@ class MLS_DB {
         ) {$charset_collate};";
 
         dbDelta($sql_sync_log);
+
+        // Media download log table
+        $table_media_log = $wpdb->prefix . MLS_TABLE_MEDIA_LOG;
+        $sql_media_log = "CREATE TABLE {$table_media_log} (
+            id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
+            media_id BIGINT(20) UNSIGNED NOT NULL,
+            listing_key VARCHAR(50) NOT NULL,
+            media_key VARCHAR(100) NOT NULL,
+            action VARCHAR(30) NOT NULL,
+            status_code INT(5) DEFAULT NULL,
+            response_time_ms INT(11) DEFAULT NULL,
+            error_message TEXT DEFAULT NULL,
+            url VARCHAR(1000) DEFAULT NULL,
+            created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+
+            PRIMARY KEY (id),
+            KEY media_id (media_id),
+            KEY listing_key (listing_key),
+            KEY action (action),
+            KEY created_at (created_at)
+        ) {$charset_collate};";
+
+        dbDelta($sql_media_log);
     }
 
     /**
@@ -253,6 +289,7 @@ class MLS_DB {
             MLS_TABLE_SYNC_STATE,
             MLS_TABLE_RATE_LIMITS,
             MLS_TABLE_SYNC_LOG,
+            MLS_TABLE_MEDIA_LOG,
         );
 
         foreach ($tables as $table) {