v0.3.1 — self-healing cron scheduling (#8)

Adds PRV_Cron_Guard hooked on init to re-schedule managed cron hooks when missing after rsync deploys. Delegates to PRV_Cron::schedule() and PRV_Prune_Cron::schedule(). Idempotent. Two wp_next_scheduled() reads per request; no DB writes unless event missing.

includes/core/class-prv-cron-guard.php

@@ -0,0 +1,69 @@
+<?php
+/**
+ * Self-healing cron guard: re-schedules managed cron events when missing.
+ *
+ * @package PrVision
+ */
+
+declare(strict_types=1);
+
+/**
+ * Idempotent guard that ensures all managed WP-Cron events are scheduled.
+ *
+ * WordPress fires the plugin activator only on activation, not on rsync
+ * file-sync updates (our deploy method). This guard runs on `init` and
+ * re-schedules any missing cron event by delegating to the canonical
+ * scheduler method for that hook -- so recurrence and first-run offset are
+ * always consistent with the activator.
+ *
+ * Managed hooks:
+ *  - `prv_weekly_probe`  -- scheduled via PRV_Cron::schedule()
+ *  - `prv_daily_prune`   -- scheduled via PRV_Prune_Cron::schedule()
+ *
+ * Hot-path cost: two `wp_next_scheduled()` checks per request. No DB
+ * writes unless an event is actually missing.
+ *
+ * Who triggers: init action (registered in PRV_Plugin::init()).
+ * Dependencies: PRV_Cron, PRV_Prune_Cron.
+ *
+ * @see class-prv-cron.php       -- Canonical weekly probe scheduler.
+ * @see class-prv-prune-cron.php -- Canonical daily prune scheduler.
+ * @see class-prv-activator.php  -- Original schedule call on activation.
+ * @package PrVision
+ */
+class PRV_Cron_Guard {
+
+	/**
+	 * Register the guard on the `init` hook.
+	 *
+	 * Side effects: Adds action for `init`.
+	 *
+	 * @return void
+	 */
+	public function register_hooks(): void {
+		add_action( 'init', array( $this, 'ensure_scheduled' ) );
+	}
+
+	/**
+	 * Ensure every managed cron hook is scheduled.
+	 *
+	 * For each managed hook, checks `wp_next_scheduled()`. If the event is
+	 * missing, delegates to the canonical scheduler (same method the
+	 * activator calls) so recurrence and offset are never duplicated here.
+	 * Calling this when all events are already scheduled is a pure no-op.
+	 *
+	 * Side effects: May call PRV_Cron::schedule() or
+	 *               PRV_Prune_Cron::schedule() when an event is missing.
+	 *
+	 * @return void
+	 */
+	public function ensure_scheduled(): void {
+		if ( ! wp_next_scheduled( PRV_CRON_HOOK ) ) {
+			PRV_Cron::schedule();
+		}
+
+		if ( ! wp_next_scheduled( PRV_Prune_Cron::PRUNE_HOOK ) ) {
+			PRV_Prune_Cron::schedule();
+		}
+	}
+}

includes/core/class-prv-plugin.php

@@ -17,13 +17,15 @@ declare(strict_types=1);
  * Who triggers: plugins_loaded action (pr-vision.php).
  * Dependencies: PRV_Upgrader, PRV_Cron, PRV_Admin_Page, PRV_Settings_Page,
  *               PRV_Settings_Controller, PRV_Costs_Page, PRV_Call_Log_Page,
- *               PRV_Call_Detail_Ajax, PRV_Prune_Cron, PRV_Collector_Registry.
+ *               PRV_Call_Detail_Ajax, PRV_Prune_Cron, PRV_Cron_Guard,
+ *               PRV_Collector_Registry.
  *
  * @see ARCHITECTURE.md             -- Boot sequence diagram.
  * @see class-prv-upgrader.php      -- Runs migrations on every boot.
  * @see class-prv-costs-page.php    -- [v0.3.0] Costs admin sub-page.
  * @see class-prv-call-log-page.php -- [v0.3.0] Call Log admin sub-page.
  * @see class-prv-prune-cron.php    -- [v0.3.0] Daily prune cron.
+ * @see class-prv-cron-guard.php    -- [v0.3.1] Self-healing cron guard.
  * @package PrVision
  */
 class PRV_Plugin {
@@ -50,6 +52,9 @@ class PRV_Plugin {
 		$prune = new PRV_Prune_Cron();
 		$prune->register_hooks();
 
+		$guard = new PRV_Cron_Guard();
+		$guard->register_hooks();
+
 		if ( is_admin() ) {
 			$page = new PRV_Admin_Page();
 			$page->register_hooks();