Add required human review gate to the Agent pipeline.

Agent web jobs now stop after Brain consolidation and enter needs_review
with a persisted review queue (blocking: high-severity, low-confidence,
sensitive-category findings; audit sample of clean clusters). Humans
decide confirm/reject/unsure/needs_clarification via new review API and
frontend queue; a finalizer applies decisions (rejections suppressed with
reason codes), performs bounded targeted reruns for clarifications,
drafts RFIs only for kept issues, and only then marks the job done and
sends the final email. Two-phase email (review-required, then final
report), per-decision feedback labels with redacted aggregate metrics,
restart recovery from job artifacts, and CLI --no-review bypass.
Classic pipeline unchanged. 65 non-LLM tests.

backend/email_sender.py

@@ -38,6 +38,22 @@ def _send(msg: EmailMessage) -> bool:
         return False
 
 
+def send_review_required(recipient_email: str, report: dict, review_url: str) -> bool:
+    if not recipient_email or not _smtp_ready():
+        return False
+    msg = EmailMessage()
+    msg["Subject"] = f"Conflict Checker - review required - {report.get('source', 'drawing set')}"
+    msg["From"] = config.SMTP_FROM or config.SMTP_USER
+    msg["To"] = recipient_email
+    review = report.get("summary", {}).get("review", {})
+    msg.set_content(
+        "Agent analysis is complete and waiting for human review.\n\n"
+        f"Required review items: {review.get('required', 0)}\n"
+        f"Review URL: {review_url}\n"
+    )
+    return _send(msg)
+
+
 def send_conflict_report(
     recipient_email: str,
     report: Dict,