fix(schema): self-heal generation_log writes on half-migrated state

A cron-triggered generation can run right after a deploy, before any
admin_init migration pass — inserts carrying the new agent_role /
prompt_version columns would fail silently on the old schema and lose
the cost row. Two-sided heal: (1) log_api_call/log_image_generation
retry the insert without the v0.18.0 columns when it fails; (2) the
db-version check now also runs on cron requests (init + wp_doing_cron),
so the schema migrates on the first cron hit, not the first admin visit.

Agent-Session: pipeline-v2-phase1-engineer-20260612

CHANGELOG.md

@@ -95,6 +95,10 @@ behavior change** to the Economy (single-pass) and multi-step publish paths.
 ### Fixed
 - ARCHITECTURE.md documented the multi-step edit stage as `edit`; the code has always
   written `polish`. Canonicalized to **`polish`** everywhere.
+- Half-migrated-schema hardening: generation_log inserts retry without the new audit
+  columns when the columns are missing (a cron run right after deploy no longer loses cost
+  rows), and the db-version self-heal now also runs on cron requests (`init` +
+  `wp_doing_cron()`), not only on `admin_init`.
 
 ## [0.17.0] - 2026-06-11
 

includes/class-prautoblogger.php

@@ -46,6 +46,10 @@ class PRAutoBlogger {
 		$this->ajax_handlers = new PRAutoBlogger_Ajax_Handlers( $this->executor->get_model_registry() );
 
 		add_action( 'admin_init', array( $this, 'on_check_db_version' ) );
+		// v0.18.0: cron requests must also self-heal the schema — after a
+		// deploy, scheduled generation can run before any admin page load,
+		// and new-column inserts would silently fail on the old schema.
+		add_action( 'init', array( $this, 'on_check_db_version_for_cron' ) );
 		add_filter( 'cron_schedules', array( $this, 'filter_add_cron_schedules' ) );
 
 		if ( is_admin() ) {
@@ -306,6 +310,21 @@ class PRAutoBlogger {
 		}
 	}
 
+	/**
+	 * Run the db-version check on cron requests (admin_init never fires
+	 * there). Gated to wp_doing_cron() so normal frontend requests pay
+	 * nothing beyond one autoloaded option read.
+	 *
+	 * Side effects: may run the same migrations as on_check_db_version().
+	 *
+	 * @return void
+	 */
+	public function on_check_db_version_for_cron(): void {
+		if ( function_exists( 'wp_doing_cron' ) && wp_doing_cron() ) {
+			$this->on_check_db_version();
+		}
+	}
+
 	/**
 	 * Add custom cron schedules (six-hourly for metrics collection).
 	 *

includes/core/class-cost-tracker.php

@@ -127,9 +127,19 @@ class PRAutoBlogger_Cost_Tracker {
 		$table = $wpdb->prefix . 'prautoblogger_generation_log';
 
 		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery
-		$wpdb->insert( $table, $log_entry->to_db_row() );
+		$inserted = $wpdb->insert( $table, $log_entry->to_db_row() );
 
-		if ( false === $wpdb->insert_id ) {
+		// Self-healing on a half-migrated schema (e.g. cron fires after a
+		// deploy but before any admin_init migration pass): retry without
+		// the v0.18.0 audit columns rather than losing the cost row.
+		if ( false === $inserted ) {
+			$legacy_row = $log_entry->to_db_row();
+			unset( $legacy_row['agent_role'], $legacy_row['prompt_version'] );
+			// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery
+			$inserted = $wpdb->insert( $table, $legacy_row );
+		}
+
+		if ( false === $inserted || false === $wpdb->insert_id ) {
 			PRAutoBlogger_Logger::instance()->error( 'Failed to log API call: ' . $wpdb->last_error, 'cost-tracker' );
 		}
 	}
@@ -179,25 +189,31 @@ class PRAutoBlogger_Cost_Tracker {
 		}
 		$table = $wpdb->prefix . 'prautoblogger_generation_log';
 
-		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery
-		$wpdb->insert(
-			$table,
-			array(
-				'post_id'           => $post_id,
-				'run_id'            => $this->run_id,
-				'stage'             => $stage,
-				'provider'          => 'cloudflare-workers-ai',
-				'model'             => $model,
-				'prompt_tokens'     => 0,
-				'completion_tokens' => 0,
-				'estimated_cost'    => $cost_usd,
-				'response_status'   => 'success',
-				'error_message'     => '',
-				'agent_role'        => PRAutoBlogger_Stage_Display_Map::default_agent_role( $stage ),
-				'prompt_version'    => $this->resolve_prompt_version( $stage, null ),
-				'created_at'        => current_time( 'mysql' ),
-			)
+		$row = array(
+			'post_id'           => $post_id,
+			'run_id'            => $this->run_id,
+			'stage'             => $stage,
+			'provider'          => 'cloudflare-workers-ai',
+			'model'             => $model,
+			'prompt_tokens'     => 0,
+			'completion_tokens' => 0,
+			'estimated_cost'    => $cost_usd,
+			'response_status'   => 'success',
+			'error_message'     => '',
+			'agent_role'        => PRAutoBlogger_Stage_Display_Map::default_agent_role( $stage ),
+			'prompt_version'    => $this->resolve_prompt_version( $stage, null ),
+			'created_at'        => current_time( 'mysql' ),
 		);
+
+		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery
+		$inserted = $wpdb->insert( $table, $row );
+
+		// Self-healing on a half-migrated schema — see log_api_call().
+		if ( false === $inserted ) {
+			unset( $row['agent_role'], $row['prompt_version'] );
+			// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery
+			$wpdb->insert( $table, $row );
+		}
 	}
 
 	/**