PR Vision v0.2.0: admin/settings interface + correctness fixes

Requirements 1-8 + all non-negotiables:

1. Model manager (CRUD): PRV_Model_Registry, prv_models v2 option, versioned
   idempotent migration from v0.1.x flat-string format, Settings page CRUD.

2. Per-model run-health: PRV_Model_Registry::update_health() after each run;
   health badges (Healthy/Retired?/Disabled/Unknown) in model table + dashboard.

3. Metric comparability: PRV_Config_Version stamps every run with config_version;
   save-bar warning on scoring-relevant changes; orphaned rows excluded by version.

4. Projected cost at save: PRV_Config::get_projected_cost(); over-cap warning;
   prv_last_run_truncated option + visible notice when cap hit mid-run.

5. Config surface: peptide set, intents, cadence (reschedules cron), budget cap;
   all validated + sanitized; next-run timestamp shown.

6. API-key three-state: not-defined / defined-ok / defined-failed; derived from
   ledger; never displays the key.

7. Run-lock: PRV_Run_Lock (transient); cron tick skips if locked; Run-now
   refuses with clear message; lock released in finally block.

8. Design fixes: dark-ink focus ring on bright fills; disabled-row full AA
   contrast (no opacity); toggle disabled on retired rows; save-bar-level
   warning (role=alert); chip text #B4BDC7 6.83:1 AA; keyboard-sortable headers
   (<button>+aria-sort); aria-live on Test chip; z-index:50 save-bar;
   run-now double-fire guard; @media print light overrides.

New: PRV_Upgrader (runs migrations on plugins_loaded, not just activation),
PRV_Config_Version, PRV_Run_Lock, PRV_Settings_Page, PRV_Settings_Renderer,
PRV_Model_Manager_Table, PRV_Model_Test_Ajax.

Tests: test-model-registry, test-run-lock, test-config-version,
       test-projected-cost, test-cron-reschedule (+ updated probe-runner,
       uninstall, bootstrap).

Schema: config_version INT column added via dbDelta (idempotent).
Uninstall: purges all v0.2 prv_* options + transients.

includes/core/class-prv-plugin.php

@@ -10,14 +10,16 @@ declare(strict_types=1);
 /**
  * Main orchestrator for the PR Vision plugin.
  *
- * Boots sub-systems in the correct order, hooks into WP, and keeps
- * the top-level file under the 300-line limit by delegating all logic
- * to specialist classes.
+ * Boots sub-systems in the correct order, runs pending data migrations,
+ * hooks into WP, and keeps the top-level file under the 300-line limit by
+ * delegating all logic to specialist classes.
  *
  * Who triggers: plugins_loaded action (pr-vision.php).
- * Dependencies: PRV_Cron, PRV_Admin_Page, PRV_Collector_Registry.
+ * Dependencies: PRV_Upgrader, PRV_Cron, PRV_Admin_Page, PRV_Settings_Page,
+ *               PRV_Collector_Registry.
  *
- * @see ARCHITECTURE.md — Boot sequence diagram.
+ * @see ARCHITECTURE.md  -- Boot sequence diagram.
+ * @see class-prv-upgrader.php -- Runs migrations on every boot.
  * @package PrVision
  */
 class PRV_Plugin {
@@ -25,18 +27,28 @@ class PRV_Plugin {
 	/**
 	 * Wire up all WordPress hooks.
 	 *
-	 * Side effects: Registers admin menus, enqueues assets, and registers the
-	 *               collector/panel registry.
+	 * Migrations run before anything reads from prv_models so the v2 format
+	 * is always in place regardless of whether the plugin was freshly activated
+	 * or just upgraded from v0.1.x while live.
+	 *
+	 * Side effects: Registers admin menus, enqueues assets, registers the
+	 *               collector/panel registry, runs data migrations.
 	 *
 	 * @return void
 	 */
 	public function init(): void {
+		// Migrations first -- must run before any config read.
+		PRV_Upgrader::run();
+
 		$cron = new PRV_Cron();
 		$cron->register_hooks();
 
 		if ( is_admin() ) {
 			$page = new PRV_Admin_Page();
 			$page->register_hooks();
+
+			$settings = new PRV_Settings_Page();
+			$settings->register_hooks();
 		}
 
 		// Register the v1 AI-visibility collector + panel.