Record batch runs beside cascades so Home lists them

A batch run opens no cascade, and FlowRun was written only from
cascade_started — so `fluksio run` showed on /runs and in `fluksio status` and
was simply absent from Home. The collector now folds the run_started and
run_finished events RunService already published. Such a record is exempt from
the staleness sweep in both places: a training step of an hour is a normal one,
and only run_finished ends it.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

backend/tests/test_metrics.py

@@ -226,11 +226,55 @@ def test_a_traceback_no_failure_ever_claims_is_dropped() -> None:
     assert collector._tracebacks == {}
 
 
+def test_a_batch_run_is_recorded_beside_the_cascades(db: Session) -> None:
+    """`fluksio run` showed on /runs and nowhere on Home.
+
+    It opens no cascade, so the collector saw its nodes and its failures with
+    no record to fold them into. The start is aged past the staleness cutoff on
+    purpose: a training step of an hour is a normal one, and only
+    `run_finished` may end a batch run.
+    """
+    collector = MetricsCollector(EventBus())
+    started = time.time() - RUN_STALE_S - 60
+    collector.handle(
+        {"type": "run_started", "run": "run-batch", "flow": FLOW, "ts": started}
+    )
+    collector.handle(
+        {
+            "type": "node_executed",
+            "flow": FLOW,
+            "node": NODE,
+            "run": "run-batch",
+            "duration_ms": 5.0,
+            "ts": started,
+        }
+    )
+    asyncio.run(collector.flush())
+
+    row = db.exec(select(FlowRun).where(FlowRun.id == "run-batch")).one()
+    assert (row.status, row.source, row.nodes) == ("running", "run", 1)
+
+    collector.handle(
+        {
+            "type": "run_finished",
+            "run": "run-batch",
+            "flow": FLOW,
+            "status": "ok",
+            "ts": started + 30,
+        }
+    )
+    asyncio.run(collector.flush())
+
+    db.expire_all()
+    row = db.exec(select(FlowRun).where(FlowRun.id == "run-batch")).one()
+    assert (row.status, row.duration_ms) == ("ok", 30_000.0)
+
+
 def test_a_failure_keeps_the_run_it_happened_in(db: Session) -> None:
     """The payload always carried it; the row used to drop it.
 
-    A batch run publishes no `cascade_started`, so there is no `FlowRun` beside
-    this — which is exactly the case that had no way of being asked about.
+    Nothing told this collector the run had started, so there is no `FlowRun`
+    beside it — the failure still has to name what it happened in.
     """
     collector = MetricsCollector(EventBus())
     ts = datetime.now(UTC).replace(second=0, microsecond=0).timestamp()