feat: add opik instrumentation to image and content pipeline

- Add optional $trace_context parameter to PRAutoBlogger_Image_Prompt_Builder
- Wrap LLM call in image_prompt_rewrite span when trace context available
- Pass trace context through from image pipeline
- Add $eval_mode parameter to content generator generate() method
- Define PRAUTOBLOGGER_EVAL_MODE constant to suppress side effects
- Add generate_eval() convenience method
- Register WP-CLI hook in main orchestrator
- Bump version to 0.13.0

prautoblogger.php

@@ -9,7 +9,7 @@
  * Plugin Name:       PRAutoBlogger
  * Plugin URI:        https://peptiderepo.com/prautoblogger
  * Description:       Monitors social media for trending topics, generates SEO-friendly blog posts using AI, and publishes them on a daily schedule with full cost tracking and self-improvement metrics.
- * Version:           0.12.3
+ * Version:           0.13.0
  * Requires at least: 6.0
  * Requires PHP:      7.4
  * Author:            PeptideRepo
@@ -35,7 +35,7 @@ if ( ! defined( 'ABSPATH' ) ) {
 | Defined here so every file in the plugin can reference paths, versions,
 | and limits without magic strings.
 */
-define( 'PRAUTOBLOGGER_VERSION', '0.12.3' );
+define( 'PRAUTOBLOGGER_VERSION', '0.13.0' );
 define( 'PRAUTOBLOGGER_DB_VERSION', '1.1.0' );
 define( 'PRAUTOBLOGGER_PLUGIN_FILE', __FILE__ );
 define( 'PRAUTOBLOGGER_PLUGIN_DIR', plugin_dir_path( __FILE__ ) );