feat(corpus): Stage A — corpus tagging fixes + prevention layer

מתקן את הבאג של תיוג שגוי לועדות ערר ומונע חזרתו:

**Code changes:**
* New MCP tool `internal_decision_upload` (chair_name+district required)
  — sole supported path for ingesting committee decisions; tags
  source_kind='internal_committee' automatically.
* Citation guard in `precedent_library_upload` rejects citations starting
  with "ערר" or "בל\"מ" with a directive to use internal_decision_upload.
* `practice_area.py` taxonomy unification: PRACTICE_AREAS now accepts
  both multi-tenant (appeals_committee/national_insurance/labor_law)
  and domain (rishuy_uvniya/betterment_levy/compensation_197) values.
  New helper `to_db_practice_area(multi_tenant, subtype) -> domain`.

**Agent docs:**
* legal-researcher (+5K): upload-tool decision flowchart, code samples
  per source_kind, district enum (ירושלים/מרכז/תל אביב/צפון/דרום/חיפה/ארצי)
* legal-ceo, legal-analyst, legal-writer, legal-qa, HEARTBEAT — taxonomy
  awareness + source_kind-aware citation patterns + research_complete
  as valid status.
* Fixed two pre-existing wrong practice_area values in examples
  (histael_hashbacha→betterment_levy, pitsuim_197→compensation_197).

Closes TaskMaster #30(parts), #38(parts), #39 (root cause).
DB-side backfill + CHECK constraints applied directly via psql:
* 11 cases.practice_area corrected (1xxx→rishuy, 8xxx→betterment)
* 6 case_law records reclassified external_upload→internal_committee
  with inferred district
* 6 chair_name backfilled from full_text (5 שרית אריאלי + 1 דפנה תמיר)
* 88 new halachot extracted for newly-uploaded precedents
  (אנטרים + ירושלים שקופה 1112/22 + אגא וכט)
* CHECK constraints: cases.practice_area enum, case_law internal⇒district

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

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

@@ -0,0 +1,104 @@
+"""MCP tools for the Internal Decisions corpus.
+
+Decisions of appeals committees (ועדות ערר) live in the same physical
+``case_law`` table as court rulings but are distinguished by
+``source_kind='internal_committee'`` and must carry ``chair_name`` +
+``district``.
+
+The existing ``precedent_library_upload`` MCP tool always stores
+``source_kind='external_upload'`` and does not accept chair/district —
+which is why **44+ existing appeals-committee decisions were tagged
+wrong**. This wrapper is the authoritative ingestion path for committee
+decisions and enforces the required metadata at the tool boundary.
+"""
+
+from __future__ import annotations
+
+import json
+
+from legal_mcp.services import internal_decisions as int_svc
+
+# Valid Hebrew district names (matches _COURT_TO_DISTRICT in service)
+VALID_DISTRICTS = {"ירושלים", "מרכז", "תל אביב", "תל-אביב", "צפון", "דרום", "חיפה", "ארצי"}
+
+
+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 internal_decision_upload(
+    file_path: str,
+    case_number: str,
+    chair_name: str,
+    district: str,
+    case_name: str = "",
+    court: str = "",
+    decision_date: str = "",
+    practice_area: str = "",
+    appeal_subtype: str = "",
+    subject_tags: list[str] | None = None,
+    summary: str = "",
+    is_binding: bool = False,
+) -> str:
+    """העלאת החלטה של ועדת ערר (internal_committee) לקורפוס הסמכותי.
+
+    Required: file_path, case_number, chair_name, district.
+    The tool enforces chair_name+district so the record cannot be saved
+    in the broken legacy mode (external_upload with empty chair/district).
+
+    Args:
+        file_path: נתיב מלא לקובץ PDF/DOCX/RTF/TXT/MD.
+        case_number: מספר הערר ("ערר (ועדות ערר - תכנון ובנייה ירושלים) 1110/20 ...").
+        chair_name: שם יו"ר הוועדה (חובה).
+        district: מחוז (ירושלים/מרכז/תל אביב/צפון/דרום/חיפה/ארצי) — חובה.
+        case_name: שם קצר.
+        court: ערכאה ("ועדת הערר לתכנון ובנייה — מחוז ירושלים").
+        decision_date: ISO date (YYYY-MM-DD), אופציונלי.
+        practice_area: rishuy_uvniya / betterment_levy / compensation_197.
+        appeal_subtype: building_permit / וכו'.
+        subject_tags: תגיות נושא.
+        is_binding: בד"כ False (ועדת ערר לא מחייבת ועדה אחרת — שכנוע אופקי).
+
+    Returns: JSON עם case_law_id, מספר chunks, halachot_pending.
+    """
+    if not file_path.strip():
+        return _err("file_path חובה")
+    if not case_number.strip():
+        return _err("case_number חובה")
+    if not chair_name.strip():
+        return _err(
+            "chair_name חובה. החלטות ועדת ערר חייבות שם יו\"ר — "
+            "בלעדיו ההחלטה לא ניתנת לחיפוש סלקטיבי לפי הרכב."
+        )
+    if not district.strip():
+        return _err(
+            "district חובה. ערכים תקפים: " + ", ".join(sorted(VALID_DISTRICTS))
+        )
+    if district.strip() not in VALID_DISTRICTS:
+        return _err(
+            f"district לא תקין: {district!r}. ערכים תקפים: "
+            + ", ".join(sorted(VALID_DISTRICTS))
+        )
+
+    try:
+        result = await int_svc.ingest_internal_decision(
+            case_number=case_number,
+            case_name=case_name,
+            court=court,
+            decision_date=decision_date or None,
+            chair_name=chair_name,
+            district=district,
+            practice_area=practice_area,
+            appeal_subtype=appeal_subtype,
+            subject_tags=subject_tags or [],
+            summary=summary,
+            is_binding=is_binding,
+            file_path=file_path,
+        )
+    except Exception as e:
+        return _err(str(e))
+    return _ok(result)