feat(learning): FU-3 — uncertainty-sampling של תור-האישור לפי מחלוקת-הפאנל (#133)

תור-אישור-ההלכות הקיים (order_by_priority, #84.3) מקדם עכשיו את ההלכות
שהפאנל התלבט עליהן: split קודם, אחר-כך incomplete — התוויות בעלות-הערך
הגבוה ביותר ללולאת-הלמידה (הכרעת-היו"ר מפרקת אי-ודאות אמיתית ומזינה את
זיקוק-ה-rubric ב-FU-4). uncertainty-sampling על סיגנל-המחלוקת האמיתי של
הפאנל, לא רק confidence-החילוץ.

- list_halachot: LEFT JOIN לאחרון-הסבבים (DISTINCT ON latest round_ts מ-
  halacha_panel_rounds) + מפתח-מיון ראשי CASE verdict split→0/incomplete→1/
  else→2, לפני מפתחות #84.3 (corroboration→confidence→age). סבבים פה-אחד
  ופריטים-ללא-סבב נשארים בזנב עם הסדר הקיים.
- panel_verdict נחשף בכל שורה (UI יכול לתייג "פיצול" + ביקורת-סדר).
- שימוש חוזר בדגל order_by_priority הקיים ובטאב הקיים — בלי מסלול/דגל
  מקביל (G2). ה-UI כבר מבקש order_by_priority=true → אפס שינוי-UI, אין
  צורך בשער-עיצוב.
- test_halacha_priority_panel_order.py: 3 בדיקות offline (SQL-capture) —
  מפתח-מחלוקת ראשי בעדיפות, FIFO ללא דליפת-CASE, panel_verdict נבחר.

Invariants: INV-G10 (capture-only, לא משנה review_status) · G1/G2 ·
INV-IA (אותו שער/טאב). רגרסיה: 76 בדיקות עברו.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

mcp-server/tests/test_halacha_priority_panel_order.py

@@ -0,0 +1,85 @@
+"""Tests for #133 / FU-3 — active uncertainty-sampling of the chair review queue.
+
+When the chair queue is requested with order_by_priority, the items the 3-judge
+panel SPLIT on (and then INCOMPLETE rounds) must float to the top — those are
+the highest-value active-learning labels (the chair's call resolves a genuine
+ambiguity and feeds rubric distillation, FU-4). This reuses the existing
+order_by_priority flag (no parallel path, G2).
+
+Runs fully OFFLINE: monkeypatches db.get_pool with a fake pool that captures the
+SQL passed to fetch, and asserts the ORDER BY / JOIN shape — no Postgres.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+import pytest
+
+from legal_mcp.services import db
+
+
+class _FakePool:
+    """Captures SQL passed to ``fetch``; returns no rows."""
+
+    def __init__(self) -> None:
+        self.queries: list[str] = []
+
+    async def fetch(self, sql: str, *args):  # noqa: ANN002, ANN201
+        self.queries.append(sql)
+        return []
+
+
+@pytest.fixture()
+def fake_pool(monkeypatch: pytest.MonkeyPatch) -> _FakePool:
+    pool = _FakePool()
+
+    async def _get_pool() -> _FakePool:
+        return pool
+
+    monkeypatch.setattr(db, "get_pool", _get_pool)
+    return pool
+
+
+def _list_sql(pool: _FakePool) -> str:
+    return next(q for q in pool.queries if "FROM halachot h" in q)
+
+
+def test_priority_order_ranks_panel_split_first(fake_pool: _FakePool) -> None:
+    asyncio.run(
+        db.list_halachot(review_status="pending_review", order_by_priority=True)
+    )
+    sql = _list_sql(fake_pool)
+    # latest-verdict join is present …
+    assert "FROM halacha_panel_rounds" in sql
+    assert "DISTINCT ON (halacha_id)" in sql
+    # … and the ORDER BY ranks split before incomplete before everything else,
+    # AHEAD of the #84.3 corroboration/confidence/age keys.
+    order = sql[sql.index("ORDER BY"):]
+    assert "WHEN 'split' THEN 0" in order
+    assert "WHEN 'incomplete' THEN 1" in order
+    rank_pos = order.index("CASE pr.verdict")
+    corr_pos = order.index("corroboration_negative")
+    conf_pos = order.index("h.confidence")
+    assert rank_pos < corr_pos < conf_pos, (
+        "panel-disagreement rank must be the PRIMARY sort key, before the "
+        "existing #84.3 corroboration/confidence ordering"
+    )
+
+
+def test_fifo_order_has_no_panel_rank(fake_pool: _FakePool) -> None:
+    """Without order_by_priority the queue stays in deterministic FIFO order —
+    the panel-rank CASE must not leak into the default ordering."""
+    asyncio.run(db.list_halachot(review_status="pending_review"))
+    sql = _list_sql(fake_pool)
+    order = sql[sql.index("ORDER BY"):]
+    assert "CASE pr.verdict" not in order
+    assert "h.case_law_id, h.halacha_index" in order
+
+
+def test_panel_verdict_selected(fake_pool: _FakePool) -> None:
+    """panel_verdict is surfaced on each row so the UI can badge *why* an item
+    is at the top of the queue (and so the order is auditable)."""
+    asyncio.run(db.list_halachot(order_by_priority=True))
+    sql = _list_sql(fake_pool)
+    assert "pr.verdict AS panel_verdict" in sql