feat: enforce import provenance exposure policy (#2)

Merge BAT-017 / REQ-021 implementation after delivery-runner implementation, independent QC, and passing GitHub Actions CI.

jarca_ledger_mcp/toss_bank_pdf.py

@@ -1,7 +1,6 @@
 from __future__ import annotations
 
 import hashlib
-import json
 import re
 from dataclasses import dataclass
 from pathlib import Path
@@ -9,6 +8,8 @@ from typing import Any
 
 import fitz
 
+from .provenance_policy import allowlisted_json_payload
+
 
 DATETIME_RE = re.compile(r"^\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}$")
 AMOUNT_RE = re.compile(r"^[+-]?\d{1,3}(?:,\d{3})*$")
@@ -32,7 +33,7 @@ class TossBankTransaction:
         return f"toss_bank_pdf:{source_hash}:{self.row_index}:{self.transaction_datetime}:{self.amount}"
 
     def raw_payload(self) -> str:
-        return json.dumps(
+        return allowlisted_json_payload(
             {
                 "row_index": self.row_index,
                 "transaction_datetime": self.transaction_datetime,
@@ -44,7 +45,7 @@ class TossBankTransaction:
                 "raw_summary": self.raw_summary,
                 "raw_lines": self.raw_lines,
             },
-            ensure_ascii=False,
+            allowed_keys=("row_index",),
         )