manually correct subsource status from starting to running (#31096)

Subsources move from starting to running lazily once they see a record
flow through, even though they are online and healthy. This has been
repeatedly brought up as confusing by users. So now, if the parent
source is running, and the subsource is starting, we override its status
to running to relfect its healthy status.

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src/catalog/src/builtin.rs

@@ -3243,6 +3243,17 @@ pub static MZ_SOURCE_STATUSES: LazyLock<BuiltinView> = LazyLock::new(|| BuiltinV
                     self_events.status <> 'ceased' AND
                     parent_events.status = 'stalled'
                 THEN parent_events.source_id
+                -- TODO: Remove this once subsources eagerly propogate their status
+                -- Subsources move from starting to running lazily once they see
+                -- a record flow through, even though they are online and healthy.
+                -- This has been repeatedly brought up as confusing by users.
+                -- So now, if the parent source is running, and the subsource is
+                -- starting, we override its status to running to relfect its healthy
+                -- status.
+                WHEN
+                    self_events.status = 'starting' AND
+                    parent_events.status = 'running'
+                THEN parent_events.source_id
                 ELSE self_events.source_id
             END AS id_to_use
         FROM