Preserve duplicate IMAP attachment filenames

[arjunrawal1]

Adds an overwrite_file option to ImapHook.download_mail_attachments() so duplicate attachment filenames can be preserved instead of silently overwriting earlier files. The default remains True, so existing behavior is unchanged unless callers opt in to suffix-based deduplication.

Closes: #65870
Related: #62321

Tests/validation:

• git diff --check
• python3 -m py_compile providers/imap/src/airflow/providers/imap/hooks/imap.py providers/imap/tests/unit/imap/hooks/test_imap.py
• Attempted PYTHONPATH=devel-common/src:providers/imap/src:. python3 -m pytest providers/imap/tests/unit/imap/hooks/test_imap.py -q, but the local environment is missing the Airflow test dependency time_machine.

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• Yes (please specify the tool below)

Generated-by: [OpenAI Codex GPT-5.5] following the guidelines

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• Read the Pull Request Guidelines for more information. Note: commit author/co-author name and email in commits become permanently public when merged.
• For fundamental code changes, an Airflow Improvement Proposal (AIP) is needed.
• When adding dependency, check compliance with the ASF 3rd Party License Policy.
• For significant user-facing changes create newsfragment: {pr_number}.significant.rst, in airflow-core/newsfragments. You can add this file in a follow-up commit after the PR is created so you know the PR number.

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Note

🛠️ Maintainer triage note for @arjunrawal1 · by @potiuk · 2026-06-18 21:56 UTC

Closing to keep the review queue clean — this draft was triaged ~9 days ago and there's been no update since:

• No worries and nothing lost — reopen it or open a fresh PR whenever you're ready to pick it back up.
• See the Pull Request quality criteria.

_{Automated triage — may be imperfect; a maintainer takes the next look.}

[boring-cyborg]

Congratulations on your first Pull Request and welcome to the Apache Airflow community! If you have any issues or are unsure about any anything please check our Contributors' Guide
Here are some useful points:

• Pay attention to the quality of your code (ruff, mypy and type annotations). Our prek-hooks will help you with that.
• In case of a new feature add useful documentation (in docstrings or in docs/ directory). Adding a new operator? Check this short guide Consider adding an example Dag that shows how users should use it.
• Consider using Breeze environment for testing locally, it's a heavy docker but it ships with a working Airflow and a lot of integrations.
• Be patient and persistent. It might take some time to get a review or get the final approval from Committers.
• Please follow ASF Code of Conduct for all communication including (but not limited to) comments on Pull Requests, Mailing list and Slack.
• Be sure to read the Airflow Coding style.
• Always keep your Pull Requests rebased, otherwise your build might fail due to changes not related to your commits.
  Apache Airflow is a community-driven project and together we are making it better 🚀.
  In case of doubts contact the developers at:
  Mailing List: dev@airflow.apache.org
  Slack: https://s.apache.org/airflow-slack

[potiuk]

@arjunrawal1 A few things need addressing before review — see our Pull Request quality criteria.

• ❌ Pre-commit / static checks — Failing: CI image checks / Static checks. See docs.

No rush.

---

Note: This comment was drafted by an AI-assisted triage tool and may contain mistakes. Once you have addressed the points above, an Apache Airflow maintainer — a real person — will take the next look at your PR. We use this two-stage triage process so that our maintainers' limited time is spent where it matters most: the conversation with you.

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Drafted-by: Claude Code (Opus 4.7); reviewed by @potiuk before posting

[potiuk]

@arjunrawal1 A few things need addressing before review — see our Pull Request quality criteria.

Issues found:

• ❌ Pre-commit / static checks: CI image checks / Static checks is failing. Run prek run --from-ref main --stage pre-commit locally and fix anything that flags. See the static-checks docs.

What to do next:

• Push a fix for the static-check failure.

No rush — take your time. We appreciate your contribution and are happy to wait for updates. If you have questions, feel free to ask on the Airflow Slack.

---

Note: This comment was drafted by an AI-assisted triage tool and may contain mistakes. Once you have addressed the points above, an Apache Airflow maintainer — a real person — will take the next look at your PR. We use this two-stage triage process so that our maintainers' limited time is spent where it matters most: the conversation with you.

[potiuk]

@arjunrawal1 A few things need addressing before review — see our Pull Request quality criteria.

• ❌ CI fails: CI image checks / Static checks (and possibly other checks — see the Checks tab for the full list).

No rush.

---

Note: This comment was drafted by an AI-assisted triage tool and may contain mistakes. Once you have addressed the points above, an Apache Airflow maintainer — a real person — will take the next look at your PR. We use this two-stage triage process so that our maintainers' limited time is spent where it matters most: the conversation with you.

---

Drafted-by: Claude Code (Opus 4.7); reviewed by @potiuk before posting

[potiuk]

@arjunrawal1 A few things need addressing before review — see our Pull Request quality criteria.

• ❌ Pre-commit / static checks. See docs.

No rush.

---

Note: This comment was drafted by an AI-assisted triage tool and may contain mistakes. Once you have addressed the points above, an Apache Airflow maintainer — a real person — will take the next look at your PR. We use this two-stage triage process so that our maintainers' limited time is spent where it matters most: the conversation with you.

---

Drafted-by: Claude Code (Opus 4.7); reviewed by @potiuk before posting

[potiuk]

@arjunrawal1 Converting to draft — this PR does not yet meet our Pull Request quality criteria.

• ❌ Pre-commit / static checks. See docs.

See the linked criteria for how to fix each item, then mark the PR "Ready for review". This is not a rejection — just an invitation to bring the PR up to standard. No rush.

Note: This comment was drafted by an AI-assisted triage tool and may contain mistakes. Once you have addressed the points above, an Apache Airflow maintainer — a real person — will take the next look at your PR. We use this two-stage triage process so that our maintainers' limited time is spent where it matters most: the conversation with you.

[potiuk]

Closing as a stale triaged draft — no update in ~9 days since the triage note. No worries: reopen this or open a fresh PR whenever you're ready to continue. Thanks for the contribution!