feat: external precedent library with auto halacha extraction

Adds a third corpus of legal authority distinct from style_corpus
(Daphna's prior decisions for voice) and case_precedents (chair-attached
quotes per case). The new corpus holds chair-uploaded court rulings and
other appeals committee decisions, with binding rules (הלכות) extracted
automatically and queued for chair approval.

Pipeline (web/app.py + services/precedent_library.py):
file → extract → chunk → Voyage embed → halacha_extractor → store +
publish progress over the existing Redis SSE channel.

Schema V7 (services/db.py): extends case_law with source_kind +
extraction status fields under a CHECK constraint pinning practice_area
to the three appeals committee domains (rishuy_uvniya, betterment_levy,
compensation_197). New precedent_chunks (vector(1024)) and halachot
tables (vector(1024) over rule_statement, IVFFlat indexes, gin on
practice_areas/subject_tags). Halachot start as pending_review; only
approved/published rows are visible to search_precedent_library.

Agents: legal-writer, legal-researcher, legal-analyst, legal-ceo,
legal-qa get search_precedent_library. legal-writer prompt explains
the three-corpus distinction and CREAC use; legal-qa now verifies that
every cited halacha resolves to an approved row in the corpus.

UI: /precedents page with four tabs — library / semantic search /
pending review (J/K nav, A/R/E shortcuts, badge count) / stats.
Reuses the existing upload-sheet progress + SSE pattern.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

mcp-server/src/legal_mcp/tools/precedent_library.py

@@ -0,0 +1,234 @@
+"""MCP tools for the External Precedent Library.
+
+This is distinct from:
+
+- ``precedents`` (case_precedents table) — chair-attached quotes scoped to
+  a specific case section. Use ``precedent_search_library`` for that.
+- ``style_corpus`` (Daphna's prior decisions) — searched via
+  ``search_decisions`` for style/voice.
+
+The precedent library is the **authoritative law** corpus: external court
+rulings and other appeals committees' decisions, with halachot extracted
+and reviewed by the chair.
+
+All halachot enter as ``pending_review`` and are invisible to search until
+the chair approves them — per project review policy.
+"""
+
+from __future__ import annotations
+
+import json
+from uuid import UUID
+
+from legal_mcp.services import db, precedent_library
+
+
+def _ok(payload) -> str:
+    return json.dumps(payload, ensure_ascii=False, indent=2, default=str)
+
+
+def _err(msg: str) -> str:
+    return json.dumps({"error": msg}, ensure_ascii=False)
+
+
+async def precedent_library_upload(
+    file_path: str,
+    citation: str,
+    case_name: str = "",
+    court: str = "",
+    decision_date: str = "",
+    source_type: str = "",
+    precedent_level: str = "",
+    practice_area: str = "",
+    appeal_subtype: str = "",
+    subject_tags: list[str] | None = None,
+    is_binding: bool = True,
+    headnote: str = "",
+    summary: str = "",
+) -> str:
+    """העלאת פסיקה חיצונית לקורפוס הסמכותי + חילוץ הלכות אוטומטי.
+
+    Args:
+        file_path: נתיב מלא לקובץ PDF/DOCX/RTF/TXT/MD.
+        citation: מראה המקום ("עע\\"מ 3975/22 ב. קרן-נכסים נ' ועדה מקומית").
+        case_name: שם קצר.
+        court: ערכאה (עליון / מנהלי / ועדת ערר ארצית / ועדת ערר מחוזית).
+        decision_date: ISO date (YYYY-MM-DD), אופציונלי.
+        source_type: court_ruling / appeals_committee.
+        precedent_level: עליון / מנהלי / ועדת_ערר_ארצית / ועדת_ערר_מחוזית.
+        practice_area: rishuy_uvniya / betterment_levy / compensation_197.
+        subject_tags: תגיות נושא (חניה, קווי_בניין, וכד').
+
+    Returns: JSON עם case_law_id, מספר chunks, מספר הלכות שנכנסו לתור אישור.
+    """
+    if not citation.strip():
+        return _err("citation חובה")
+    try:
+        result = await precedent_library.ingest_precedent(
+            file_path=file_path,
+            citation=citation,
+            case_name=case_name,
+            court=court,
+            decision_date=decision_date or None,
+            source_type=source_type,
+            precedent_level=precedent_level,
+            practice_area=practice_area,
+            appeal_subtype=appeal_subtype,
+            subject_tags=subject_tags or [],
+            is_binding=is_binding,
+            headnote=headnote,
+            summary=summary,
+        )
+    except Exception as e:
+        return _err(str(e))
+    return _ok(result)
+
+
+async def precedent_library_list(
+    practice_area: str = "",
+    court: str = "",
+    precedent_level: str = "",
+    source_type: str = "",
+    search: str = "",
+    limit: int = 100,
+) -> str:
+    """רשימה של פסיקה בקורפוס הסמכותי, עם פילטרים."""
+    rows = await precedent_library.list_precedents(
+        practice_area=practice_area,
+        court=court,
+        precedent_level=precedent_level,
+        source_type=source_type,
+        search=search,
+        limit=limit,
+    )
+    return _ok(rows)
+
+
+async def precedent_library_get(case_law_id: str) -> str:
+    """פסיקה ספציפית עם כל ההלכות שלה (כולל ממתינות לאישור)."""
+    try:
+        cid = UUID(case_law_id)
+    except ValueError:
+        return _err("case_law_id לא תקין")
+    record = await precedent_library.get_precedent(cid)
+    if not record:
+        return _err("פסיקה לא נמצאה")
+    return _ok(record)
+
+
+async def precedent_library_delete(case_law_id: str) -> str:
+    """מחיקת פסיקה מהקורפוס. cascade: chunks + halachot."""
+    try:
+        cid = UUID(case_law_id)
+    except ValueError:
+        return _err("case_law_id לא תקין")
+    ok = await precedent_library.delete_precedent(cid)
+    return _ok({"deleted": ok, "case_law_id": case_law_id})
+
+
+async def precedent_extract_halachot(case_law_id: str) -> str:
+    """הרצה מחדש של חילוץ ההלכות לפסיקה קיימת. הלכות קודמות נמחקות."""
+    try:
+        cid = UUID(case_law_id)
+    except ValueError:
+        return _err("case_law_id לא תקין")
+    try:
+        result = await precedent_library.reextract_halachot(cid)
+    except Exception as e:
+        return _err(str(e))
+    return _ok(result)
+
+
+async def search_precedent_library(
+    query: str,
+    practice_area: str = "",
+    court: str = "",
+    precedent_level: str = "",
+    appeal_subtype: str = "",
+    is_binding: bool | None = None,
+    subject_tag: str = "",
+    limit: int = 10,
+    include_halachot: bool = True,
+) -> str:
+    """חיפוש סמנטי בקורפוס הפסיקה הסמכותית.
+
+    מחזיר תוצאות מעורבות: הלכות (rule-level, מאושרות בלבד) + קטעי טקסט
+    (passage-level). הלכות מקבלות boost קל בדירוג כי הן מזוקקות מראש.
+
+    Args:
+        query: שאילתת חיפוש בעברית.
+        practice_area: rishuy_uvniya / betterment_levy / compensation_197.
+        court: סינון לפי ערכאה (substring).
+        precedent_level: עליון / מנהלי / ועדת_ערר_ארצית / ועדת_ערר_מחוזית.
+        appeal_subtype: סינון לתת-סוג.
+        is_binding: True/False (None = ללא סינון).
+        subject_tag: סינון לפי תגית נושא (לדוגמה "מועד_קביעת_שומה").
+        limit: מספר תוצאות מקסימלי.
+        include_halachot: האם לכלול הלכות (ברירת מחדל: כן).
+
+    Returns: רשימה מדורגת. כל פריט הוא {"type": "halacha"|"passage", "score", ...}.
+    """
+    if not query or len(query.strip()) < 2:
+        return json.dumps([], ensure_ascii=False)
+    results = await precedent_library.search_library(
+        query=query.strip(),
+        practice_area=practice_area,
+        court=court,
+        precedent_level=precedent_level,
+        appeal_subtype=appeal_subtype,
+        is_binding=is_binding,
+        subject_tag=subject_tag,
+        limit=limit,
+        include_halachot=include_halachot,
+    )
+    return _ok(results)
+
+
+async def halacha_review(
+    halacha_id: str,
+    status: str,
+    reviewer: str = "דפנה",
+    rule_statement: str = "",
+    reasoning_summary: str = "",
+    subject_tags: list[str] | None = None,
+    practice_areas: list[str] | None = None,
+) -> str:
+    """אישור / דחייה / עריכה של הלכה שחולצה אוטומטית.
+
+    Args:
+        halacha_id: מזהה ההלכה.
+        status: pending_review / approved / rejected / published.
+        reviewer: שם המאשר (ברירת מחדל: דפנה).
+        rule_statement: עריכת ניסוח הכלל (ריק = ללא שינוי).
+        reasoning_summary: עריכת תמצית ההיגיון (ריק = ללא שינוי).
+        subject_tags: עריכת תגיות (None = ללא שינוי).
+        practice_areas: עריכת תחומים (None = ללא שינוי).
+    """
+    if status not in {"pending_review", "approved", "rejected", "published"}:
+        return _err(
+            "status לא חוקי. ערכים תקינים: "
+            "pending_review / approved / rejected / published"
+        )
+    try:
+        hid = UUID(halacha_id)
+    except ValueError:
+        return _err("halacha_id לא תקין")
+
+    row = await db.update_halacha(
+        halacha_id=hid,
+        review_status=status,
+        reviewer=reviewer,
+        rule_statement=rule_statement or None,
+        reasoning_summary=reasoning_summary or None,
+        subject_tags=subject_tags,
+        practice_areas=practice_areas,
+    )
+    if row is None:
+        return _err("הלכה לא נמצאה")
+    return _ok(row)
+
+
+async def halachot_pending(limit: int = 100) -> str:
+    """תור ההלכות הממתינות לאישור (review_status='pending_review')."""
+    rows = await db.list_halachot(review_status="pending_review", limit=limit)
+    return _ok(rows)