Do not show @timestamp in logs in UI

[k-popov]

When:

• airflow3 is deployed into k8s with community helm chart
• airflow is configured to read logs from elasticsearch where fluentbit is pushing them by reading output of task pods
• configuration is the following (partial)

[core]
remote_logging = True
[elasticsearch]
json_format = True
write_stdout = True

after a task is already finished an additional @timestamp field is displayed in web UI which duplicates information in the main timestamp (at the beginning of line):

The patch is not including the @timestamp field itself but still performs mapping it into timestamp field is the latter is not present. With the proposed patch there is no duplicated information on timestamp, the log looks cleaner:

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[boring-cyborg]

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[potiuk]

Good catch, and precisely diagnosed. The old filter kept @timestamp in the output set and only removed it via .pop() when timestamp was absent — so whenever a hit carried both, which is the normal case once a shipper adds @timestamp alongside the timestamp the supervisor already wrote, the pop never ran and the field leaked into the UI.

Reading it from hit_dict as a fallback source instead of filtering it in is the right shape, and the @timestamp-only path still maps correctly since TASK_LOG_FIELDS contains timestamp. Fixing both providers symmetrically with the same both-present regression test in each is exactly right.

I pushed the docstring fix myself so this didn't need another round-trip from you — the OpenSearch handler's docstring had picked up "ES" from the elasticsearch copy.

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Drafted-by: Claude Code (Opus 5); reviewed by @potiuk before posting

[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.