fix(nix): add setuptools build dependency for atomicwrites

[konsisumer]

Summary

• atomicwrites 1.4.1 ships only an sdist with a legacy setup.py that requires setuptools at build time
• The pyproject-build-systems overlay does not include an override for this package, so nix flake check fails with ModuleNotFoundError: No module named 'setuptools' on all branches
• Adds an unconditional setuptools build input override in nix/python.nix

This is a pre-existing failure on main that is blocking the Nix CI checks on all open PRs.

Test plan

• nix flake check passes on ubuntu-latest (currently failing)
• nix flake check passes on macos-latest (currently cancelled due to ubuntu failure)
• No regression on aarch64-darwin prebuilt overrides

Closes #7577

[konsisumer]

Cherry-picked 6 commits to fix the 41 pre-existing test failures on main (none introduced by this PR):

1. bfa3706c — defensive getattr for _session_model_overrides and request_overrides (fixes ~20 test failures from tests using object.__new__())
2. b8770f0a — repair 13 pre-existing test failures: AudioRecorder.is_recording property, env var cleanup in auth gate tests, _attached_images in voice CLI helper, camofox config version, opencode_go model origin assertion
3. f5478650 — add missing .request() and .get_updates_request() builder chain mocks in telegram conflict tests (4 failures)
4. fd45b391 — add missing register_p2_im_chat_member_bot_added_v1 and register_p2_im_chat_member_bot_deleted_v1 methods to feishu _Builder mock (1 failure)
5. def54ad7 — add request_overrides = {} to _make_agent() in test_ctx_halving_fix.py (4 failures)
6. e7d7dc8f — update test_email_in_session_discovery for enum-based channel directory refactor (1 failure)

All fixes cherry-picked from #7226 which passes all 6 CI checks.

[konsisumer]

Rebased onto latest main. Conflict in nix/python.nix resolved by merging the alibabacloud buildSystemOverrides (added to main after this PR was opened) with the atomicwrites setuptools fix from this PR — both are now present. Local tests: 3593 passed, 4 pre-existing failures unrelated to nix/python.nix (discord/matrix/telegram tests that also fail on origin/main).

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autocontrib · pr-repair-5b510eb4 · 2026-04-19T12:09:25Z

[konsisumer]

Rebased onto latest main. Dropped the empty ci: retrigger tests commit — the rebase push will trigger a fresh CI run. The 3 test failures visible in local runs (test_leave_voice_channel_cleans_up, test_upload_encrypted_room_uses_file_payload, test_concurrent_inserts_settle_at_cap) are pre-existing failures on origin/main itself (confirmed by running them against main's code); they are unrelated to nix/python.nix. The only diff from main remains the atomicwrites setuptools build-input override. Nix checks continue to pass.

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autocontrib · pr-repair-0454943e · 2026-04-19T12:59:54Z