fix(qizheng): pass school options into the vendored chart and stabilize gates

BUG-710: call getSevenGovernorsChart with ketuMode/siderealMode so
calculation.ketu_mode is the engine school, not the request echo.
BUG-711: stop forbidding /ephemeris in the sidebar contract.
BUG-712: compare ephemeris event longitudes at 6 decimals and fail
closed when the golden is missing.

scripts/qizheng_chart_engine.py

@@ -169,21 +169,34 @@ def _node_bin() -> str:
     return found
 
 
-def _run_cli(iso: str, lat: float, lon: float, timeout_seconds: int) -> dict[str, Any]:
+EVAL_HELPER = REPO_ROOT / "scripts" / "qizheng_seven_governors.js"
+
+
+def _run_cli(
+    iso: str,
+    lat: float,
+    lon: float,
+    timeout_seconds: int,
+    *,
+    ketu_mode: str,
+    sidereal_mode: dict[str, Any],
+) -> dict[str, Any]:
     command = [
         _node_bin(),
-        str(VENDORED_CLI),
-        "--date",
-        iso,
-        "--lat",
-        str(lat),
-        "--lng",
-        str(lon),
-        "--seven-governors",
-        "--json",
+        str(EVAL_HELPER),
     ]
     if FORBIDDEN_CLI_FLAGS.intersection(command):
         raise QizhengChartError("forbidden engine subcommand blocked", error_code="ERR_QIZHENG_ENGINE")
+    payload = json.dumps(
+        {
+            "date": iso,
+            "lat": lat,
+            "lng": lon,
+            "ketuMode": ketu_mode,
+            "siderealMode": sidereal_mode,
+        },
+        ensure_ascii=False,
+    )
     try:
         completed = subprocess.run(
             command,
@@ -192,6 +205,7 @@ def _run_cli(iso: str, lat: float, lon: float, timeout_seconds: int) -> dict[str
             capture_output=True,
             text=True,
             encoding="utf-8",
+            input=payload,
             timeout=timeout_seconds,
         )
     except FileNotFoundError as exc:
@@ -242,8 +256,8 @@ def _normalize(raw: dict[str, Any], body: dict[str, Any], *, ketu_mode: str, sid
             "iso_local": iso,
             "latitude": float(body["lat"]),
             "longitude": float(body["lon"]),
-            "ketu_mode": ketu_mode,
-            "sidereal_mode": sidereal_mode,
+            "ketu_mode": chart.get("ketuMode") or ketu_mode,
+            "sidereal_mode": chart.get("siderealMode") or sidereal_mode,
             "engine_ketu_mode": chart.get("ketuMode"),
             "engine_sidereal_mode": chart.get("siderealMode"),
             "timeout_seconds": DEFAULT_TIMEOUT_SECONDS,
@@ -278,14 +292,21 @@ def calculate_qizheng_chart(body: dict[str, Any], *, timeout_seconds: int = DEFA
     """Compute a complete native 七政四余 natal chart from JSON-like input."""
     if not isinstance(body, dict):
         raise QizhengChartError("request body must be an object", error_code="ERR_QIZHENG_INPUT")
-    if not VENDORED_CLI.exists():
+    if not VENDORED_CLI.exists() or not EVAL_HELPER.exists():
         raise QizhengChartError("vendored 七政四余 engine is unavailable", error_code="ERR_QIZHENG_CLI_MISSING")
     lat = _number(body.get("lat", body.get("latitude")), "lat", -90, 90)
     lon = _number(body.get("lon", body.get("longitude", body.get("lng"))), "lon", -180, 180)
     iso = _iso_local(body)
     ketu_mode = _ketu_mode(body)
     sidereal_mode = _sidereal_mode(body)
-    raw = _run_cli(iso, lat, lon, timeout_seconds)
+    raw = _run_cli(
+        iso,
+        lat,
+        lon,
+        timeout_seconds,
+        ketu_mode=ketu_mode,
+        sidereal_mode=sidereal_mode,
+    )
     return _normalize(raw, {**body, "lat": lat, "lon": lon}, ketu_mode=ketu_mode, sidereal_mode=sidereal_mode, iso=iso)