fix: ops pipeline — rate limit, validation cycle, snapshots, config query, rejection reason

- Polygon rate limit env-configurable, default 5 (free tier)
- v3_engine_enabled reads from JSONB config column correctly
- Validation cycle (outcome eval + metrics) wired into scheduler hourly
- Daily portfolio/risk snapshots after 16:30 ET with idempotency
- Prediction snapshot price fallback from positions table
- Order rejection_reason + rejected_at persisted on insert
- Lake-publisher scaled to 0 replicas (redundant)
- Test fix: isolate per-type rate limit tests from Polygon global

services/aggregation/worker.py

@@ -316,19 +316,22 @@ async def fetch_probabilistic_scoring_enabled(pool: asyncpg.Pool) -> bool:
 # ---------------------------------------------------------------------------
 
 _V3_ENGINE_FLAG_QUERY = """
-SELECT value FROM risk_configs WHERE key = 'v3_engine_enabled'
+SELECT config->>'v3_engine_enabled' AS enabled
+FROM risk_configs
+WHERE name = 'default' AND active = TRUE
+LIMIT 1
 """
 
 
 async def _read_v3_flag(pool: asyncpg.Pool) -> bool:
-    """Read v3_engine_enabled from risk_configs. Default False on error.
+    """Read v3_engine_enabled from risk_configs JSONB. Default False on error.
 
     Requirements: 19.3, 19.6
     """
     try:
         row = await pool.fetchrow(_V3_ENGINE_FLAG_QUERY)
-        if row:
-            return str(row["value"]).lower() in ("true", "1", "yes")
+        if row and row["enabled"] is not None:
+            return row["enabled"].lower() in ("true", "1", "yes")
         return False
     except Exception as e:
         logger.warning("Failed to read v3_engine_enabled flag: %s", e)