A01: Fix scheduler aggregation to not mask stale/failed sources

Bug: has_any_success allowed one healthy source to give overall 'ready'
when another source was stale/not_started/running — masking failures.

Fix:
- Added has_any_stale and has_any_running tracking
- Overall status is 'degraded' if ANY source is failed/stale/running
- Overall status is 'ready' ONLY when ALL enabled sources are healthy
- 'not_started' when no sources are enabled
- readiness (ready flag) still NOT blocked by import health (A01 requirement)

Verification:
- 7/7 readiness tests pass
- 124/124 Python tests pass (1 skipped)
- Stale source now shows 'degraded' instead of 'ready'
- Failed source still shows 'degraded'
- All healthy sources show 'ready'

apps/api/app/readiness.py

@@ -80,6 +80,8 @@ def readiness_report(
         source_health: dict[str, dict[str, object]] = {}
         has_any_failure = False
         has_any_success = False
+        has_any_stale = False
+        has_any_running = False
         for source in enabled_sources:
             latest_run = session.scalar(
                 select(CommunityImportRun)
@@ -115,13 +117,20 @@ def readiness_report(
                 has_any_success = True
             elif latest_run.status == "failed":
                 has_any_failure = True
-        # Overall status: "degraded" if any source failed, "ready" if all healthy, "stale" if no failures but stale
-        if has_any_failure:
+            elif stale:
+                has_any_stale = True
+            elif latest_run.status == "running":
+                has_any_running = True
+        # Overall status: never mask failures with success of another source
+        # "degraded" if any source failed/stale/running
+        # "ready" only when ALL enabled sources are healthy
+        # "not_started" when no sources are enabled
+        if has_any_failure or has_any_stale or has_any_running:
             scheduler_status = "degraded"
-        elif has_any_success:
+        elif has_any_success and len(source_health) > 0:
             scheduler_status = "ready"
         else:
-            scheduler_status = "stale" if enabled_sources else "not_started"
+            scheduler_status = "not_started"
         components["community_scheduler"] = {"status": scheduler_status, "sources": source_health}
     except Exception:
         components["community_scheduler"] = {"status": "unknown", "sources": {}}