feat: add seatmap context panel and smoke checks

backend/app/ledger_runtime.py

@@ -3,6 +3,7 @@ from __future__ import annotations
 import hashlib
 import json
 from pathlib import Path
+from urllib.parse import quote
 
 from fastapi import HTTPException
 from fastapi.responses import FileResponse, Response
@@ -88,7 +89,7 @@ def build_business_ledger_default_response(cur) -> Response:
     headers = {
         "Content-Disposition": 'inline; filename="business-ledger-default.xlsx"',
         "X-Source-Filename": "business-ledger-default.xlsx",
-        "X-Original-Filename": filename,
+        "X-Original-Filename": quote(filename),
         "Cache-Control": "no-store, no-cache, must-revalidate, max-age=0",
         "Pragma": "no-cache",
     }