Fix missing _team_name on DagRun before some listener calls

[kacpermuda]

In multi-team deployments the scheduler fires on_dag_run_running / success / failed listener hooks from several code paths. Before this change, DagRun._team_name was not guaranteed to be set when those hooks fired, so OpenLineage (and any other plugin reading _team_name) would miss the team on some events.

_team_name is a private attribute — it is not part of any public API and is not guaranteed to be present on every DagRun object a listener receives. Since the value is already cached in self._dag_id_to_team_name for metrics purposes, setting it consistently before each hook fires adds no cost. Listeners that wish to use it should treat it as best-effort and guard accordingly.

This PR ensures _team_name is stamped on every ORM DagRun object before notify_dagrun_state_changed() is called, covering all five listener code paths. The stamping is cheap: _get_team_names_for_dag_ids caches results in self._dag_id_to_team_name for the lifetime of a scheduler loop, so most calls are a dict read with no DB query. I've also added comments to the existing stamping paths, just to make sure it's clear why it's done before listener call.

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• Yes — Claude Code (Sonnet 4.6)

Generated-by: Claude Code (Sonnet 4.6) following the guidelines

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[kacpermuda]

cc @ferruzzi , FYI as I see that you worked on adding this before

[uranusjr]

I would introduce a helper (say _stamp_team_names) to do the stamping instead of repeating the same logic multiple times. It would also help clean up the verbose comment added on every stamping block.

[kacpermuda]

I would introduce a helper (say _stamp_team_names) to do the stamping instead of repeating the same logic multiple times. It would also help clean up the verbose comment added on every stamping block.

@uranusjr Extracted the logic to a separate helper, ptal

[ferruzzi]

Clearing the db at the beginning of the tests should be a code smell. I believe this issue was fixed in #69093, if not, then we need to figure out what tests are not cleaning up after themselves and fix them.

[kacpermuda]

Correct, I should have just used the fixtures currently present. Adjusted the code.

[ferruzzi]

These tests all have a pretty big repetitive block at the top, maybe move the setup into a shared fixture if none of the existing fixtures do what you need? look at the testing_team fixture though, I think that covers most/all of this boilerplate.

[kacpermuda]

Correct, used testing_team and testing_dag_bundle fixtures instead, and linked them together in a new small fixture that I reused in all tests. Should be clean now, thanks for spotting that.

[vatsrahul1001]

@kacpermuda can you resolve comments?

[kacpermuda]

@vatsrahul1001 addressed all the comments

[vatsrahul1001]

LGTM!, can be merged after code owners review

[jason810496]

Thanks, LGTM overall.