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.

tests/unit/test-config-version.php

@@ -0,0 +1,120 @@
+<?php
+/**
+ * Tests for PRV_Config_Version: config hash, bump, version records.
+ *
+ * @package PrVision
+ */
+
+declare(strict_types=1);
+
+require_once __DIR__ . '/../bootstrap.php';
+
+echo "=== PRV Config Version Tests ===\n";
+
+// Shared API key constant.
+if ( ! defined( 'PRV_OPENROUTER_API_KEY' ) ) {
+	define( 'PRV_OPENROUTER_API_KEY', 'sk-or-test-key' );
+}
+if ( ! defined( 'PRV_CF_ACCOUNT_ID' ) ) {
+	define( 'PRV_CF_ACCOUNT_ID', '' );
+}
+if ( ! defined( 'PRV_CF_GATEWAY_ID' ) ) {
+	define( 'PRV_CF_GATEWAY_ID', '' );
+}
+
+// ── Test: maybe_seed_initial_version creates a v1 record ────────────────
+
+prv_test_reset();
+PRV_Model_Registry::run_migration_v2();
+PRV_Config_Version::maybe_seed_initial_version();
+
+$versions = PRV_Config_Version::get_all_versions();
+prv_assert( count( $versions ) >= 1, 'seed: at least 1 version record after initial seed' );
+prv_assert_equals( 1, (int) $versions[0]['version'], 'seed: first version number is 1' );
+prv_assert( ! empty( $versions[0]['hash'] ), 'seed: version has a hash' );
+prv_assert_equals( 1, PRV_Config_Version::get_active_version(), 'seed: active version is 1' );
+
+// ── Test: maybe_seed_initial_version is idempotent ───────────────────────
+
+PRV_Config_Version::maybe_seed_initial_version();
+prv_assert_equals( 1, count( PRV_Config_Version::get_all_versions() ), 'seed idempotent: still 1 version after second seed call' );
+
+// ── Test: bump when config unchanged returns null ────────────────────────
+
+prv_test_reset();
+PRV_Model_Registry::run_migration_v2();
+PRV_Config_Version::maybe_seed_initial_version();
+
+$bump = PRV_Config_Version::bump_version_if_changed();
+prv_assert( null === $bump, 'bump: returns null when config unchanged' );
+prv_assert_equals( 1, PRV_Config_Version::get_active_version(), 'bump: active version stays 1 when config unchanged' );
+
+// ── Test: bump after scoring-relevant change creates new version ─────────
+
+prv_test_reset();
+PRV_Model_Registry::run_migration_v2();
+PRV_Config_Version::maybe_seed_initial_version();
+
+// Change the model list (scoring-relevant).
+$all = PRV_Model_Registry::get_all();
+PRV_Model_Registry::add( 'anthropic/claude-3-haiku', 'openrouter', true, 'New model' );
+
+$new_ver = PRV_Config_Version::bump_version_if_changed();
+prv_assert( null !== $new_ver, 'bump: returns new version number when config changed' );
+prv_assert_equals( 2, (int) $new_ver, 'bump: new version is 2' );
+prv_assert_equals( 2, PRV_Config_Version::get_active_version(), 'bump: active version updated to 2' );
+prv_assert_equals( 2, count( PRV_Config_Version::get_all_versions() ), 'bump: 2 version records exist' );
+
+// ── Test: would_change detects a config change ───────────────────────────
+
+prv_test_reset();
+PRV_Model_Registry::run_migration_v2();
+PRV_Config_Version::maybe_seed_initial_version();
+
+$original_hash = PRV_Config_Version::compute_hash();
+prv_assert( false === PRV_Config_Version::would_change( $original_hash ), 'would_change: false when hash is current' );
+
+// Modify config.
+PRV_Model_Registry::add( 'x/new-model', 'openrouter', true );
+$new_hash = PRV_Config_Version::compute_hash();
+prv_assert( true === PRV_Config_Version::would_change( $new_hash ), 'would_change: true when config differs' );
+
+// ── Test: compute_hash is stable for same config ─────────────────────────
+
+prv_test_reset();
+PRV_Model_Registry::run_migration_v2();
+$h1 = PRV_Config_Version::compute_hash();
+$h2 = PRV_Config_Version::compute_hash();
+prv_assert_equals( $h1, $h2, 'compute_hash: stable for same config' );
+
+// ── Test: config_version stamped on probe result ─────────────────────────
+
+prv_test_reset();
+PRV_Model_Registry::run_migration_v2();
+PRV_Config_Version::maybe_seed_initial_version();
+prv_assert_equals( 1, PRV_Config_Version::get_active_version(), 'version stamp: active version is 1 before run' );
+
+// Verify the runner writes config_version to DB (check the last DB insert args).
+$GLOBALS['prv_test_state']['options']['prv_peptides']       = [ [ 'slug' => 'bpc-157', 'label' => 'BPC-157' ] ];
+$GLOBALS['prv_test_state']['options']['prv_prompt_intents'] = [ 'what is {peptide}' ];
+$GLOBALS['prv_test_state']['options']['prv_models']         = [
+	[ 'id' => 'mdl_test01', 'slug' => 'perplexity/sonar', 'provider' => 'perplexity', 'enabled' => true, 'note' => '', 'health_status' => 'unknown', 'health_probed' => 0, 'health_errors' => 0, 'health_run_id' => null ]
+];
+$GLOBALS['prv_test_state']['options'][ PRV_Model_Registry::VERSION_KEY ] = PRV_Model_Registry::SCHEMA_VERSION;
+
+$cited_body = json_encode([
+	'choices'   => [['message' => ['content' => 'test']]],
+	'citations' => ['https://peptiderepo.com/bpc-157/'],
+	'usage'     => ['total_tokens' => 50],
+]);
+$GLOBALS['prv_test_state']['remote_posts'] = [
+	['response' => ['code' => 200], 'body' => $cited_body],
+];
+
+$runner = new PRV_Probe_Runner( new PRV_Cost_Ledger() );
+$result = $runner->run();
+prv_assert_equals( 1, $result['probed'], 'version stamp: runner completes 1 probe' );
+// The prv_active_config_version persists after the run.
+prv_assert_equals( 1, PRV_Config_Version::get_active_version(), 'version stamp: config version unchanged after run' );
+
+exit( prv_test_summary() );