fix(cadastre,nspd_sync): SQL syntax bugs surfaced by ekb_full v2

Three distinct SQL syntax errors caught from worker logs:

1. **upsert_zouit** (bulk_harvest.py:940) — trailing comma after 4326
   in ST_Transform(..., 3857), 4326,) → 'syntax error at or near ")"'.
   Hit on 8+ quarters in 0108 block (66:41:0108055/61/69/77 etc).
   Likely introduced by ruff-format auto-comma on closing paren.

2. **nspd_sync** (nspd_sync.py:120) — `:fetched_at_utc::timestamptz`
   psycopg double-colon trap → 'syntax error at or near ":"'.
   Crashed legacy on-demand harvest_quarter called from analyze.

3. **job_settings** (job_settings.py:224) — `:extra_config::jsonb`
   same double-colon trap in admin settings UPDATE.

All converted to CAST(:x AS type) pattern (psycopg v3 safe).

40 tests still passing.

backend/app/services/cadastre/bulk_harvest.py

@@ -937,7 +937,7 @@ def upsert_zouit(db: Session, feature: NSPDBulkFeature, source: str = "search")
                     ST_Multi(
                         ST_Transform(
                             ST_SetSRID(ST_GeomFromGeoJSON(CAST(:geom AS text)), 3857),
-                            4326,
+                            4326
                         )
                     )
                 ELSE NULL END,

backend/app/services/job_settings.py

@@ -221,7 +221,7 @@ def update(
         params["rate_ms"] = rate_ms if rate_ms > 0 else None
 
     if extra_config is not None:
-        sets.append("extra_config = :extra_config::jsonb")
+        sets.append("extra_config = CAST(:extra_config AS jsonb)")
         import json
 
         params["extra_config"] = json.dumps(extra_config, ensure_ascii=False)

backend/app/workers/tasks/nspd_sync.py

@@ -117,7 +117,7 @@ _UPSERT_SQL = text(
         :red_lines_count, :engineering_count, :zouit_count, :risks_count, :total_features,
         CAST(:features_json AS jsonb),
         CAST(:layers_fetched AS text[]),
-        :fetched_at_utc::timestamptz,
+        CAST(:fetched_at_utc AS timestamptz),
         :harvest_duration_ms,
         :harvest_error,
         :region_code