Phase 3 v2: all step automations + cross-cutting UI

Step automations (six more):
- Step 3 (Core): current vs latest WP version, db upgrade flag, auto-
  update policy, safe-update sequence reminder.
- Step 5 (Theme): parent/child detection, customisation warning when
  non-default theme without child, theme update available, inactive
  theme list.
- Step 6 (Visual): mShots screenshot URL, key-page HEAD checks (home,
  login, posts page, WC shop/cart/checkout), mixed-content scan.
- Step 7 (Performance): keyless PageSpeed Insights v5 API (mobile +
  desktop, cached 12h, skipped on .local), caching plugin detection,
  heavy-image scan (>500KB).
- Step 10 (Uptime): monitoring plugin detection (ManageWP, MainWP,
  Jetpack, WP Umbrella, UptimeRobot), www/non-www canonical check.
- Step 12 (Wrap-up): cross-step rollup — bad/warn counts, blocked
  steps, top examples for the technician's final glance.

Cross-cutting:
- Sticky step-index sidebar with status dots per step (the linear-
  stepper alternative that keeps the overview).
- 'Stop & escalate' summary card at top listing blocked steps with
  escalation guidance and notes.
- Previous-session snapshot stored on finish; diff banner on the next
  session shows new/resolved/changed counts.
- HTML report builder (printable, inline-styled). Download HTML,
  Download Markdown, Copy, and Email actions on the finish panel.
  Email uses wp_mail with text/html.

Smoke-tested on testsite: all 12 steps return findings (5/9/4 by level
on a fresh local install), admin page renders with all UI markers,
HTML report is 26KB, Markdown report is 13KB, prev-session diff banner
appears on second session.

Deferred:
- hc-5ix.27 self-hosted update channel — needs hosting infra.
- Full PDF report — would need vendoring Dompdf.
- Step 3 safe-mode update wizard — worth its own bead.

includes/steps/120-wrap-up.php

@@ -13,4 +13,57 @@ return new class extends WPH_Step {
             'If anything was flagged that needs a separate quote or client decision, send that communication now rather than leaving it',
         ];
     }
+
+    public function autocheck(array $session_state): array {
+        // Roll up all 'bad' and 'warn' findings from other steps into a wrap-up summary.
+        $bad = [];
+        $warn = [];
+        $blocked = [];
+        foreach (WPH_Steps::instance()->all() as $sid => $s) {
+            if ($sid === 'wrap_up') continue;
+            // Pull stored autocheck results from session data (we get session_state passed in).
+            $stored = $session_state['autocheck'][$sid] ?? null;
+            if ($stored && !empty($stored['findings'])) {
+                foreach ($stored['findings'] as $finding) {
+                    $label = $s->title() . ' → ' . $finding['label'];
+                    if ($finding['level'] === 'bad')  $bad[]  = $label . ' (' . $finding['value'] . ')';
+                    if ($finding['level'] === 'warn') $warn[] = $label . ' (' . $finding['value'] . ')';
+                }
+            }
+            $step_state = $session_state['steps'][$sid] ?? null;
+            if (is_array($step_state) && ($step_state['status'] ?? '') === 'blocked') {
+                $blocked[] = $s->title();
+            }
+        }
+        $f = [];
+        $f[] = $this->finding(
+            'bad_count',
+            count($bad) > 0 ? 'bad' : 'ok',
+            'Critical findings',
+            (string) count($bad),
+            $bad ? implode(' · ', array_slice($bad, 0, 6)) . (count($bad) > 6 ? ' …' : '') : 'No bad-level findings across steps.'
+        );
+        $f[] = $this->finding(
+            'warn_count',
+            count($warn) > 0 ? 'warn' : 'ok',
+            'Warnings',
+            (string) count($warn),
+            $warn ? implode(' · ', array_slice($warn, 0, 8)) . (count($warn) > 8 ? ' …' : '') : ''
+        );
+        $f[] = $this->finding(
+            'blocked_steps',
+            count($blocked) > 0 ? 'bad' : 'ok',
+            'Blocked steps',
+            (string) count($blocked),
+            $blocked ? implode(', ', $blocked) : ''
+        );
+        $f[] = $this->finding(
+            'tip_copy',
+            'info',
+            'Tip',
+            'paste this into the client record',
+            'Click Copy to clipboard on the finish screen — the full Markdown report is also downloadable.'
+        );
+        return $f;
+    }
 };