feat(feishu): add ignore_at_all config to opt out of @everyone triggering the bot

[DavidMetcalfe]

Closes #33723

Problem

In Feishu group chats, the bot always responds to @所有人/@everyone mentions because _mentions_self() in plugins/platforms/feishu/adapter.py short-circuits to True whenever @_all appears in the raw message content. In announcement-heavy groups this produces unwanted bot responses that can't be disabled.

Solution

Adds an opt-in config so @_all alone no longer triggers the bot:

• Env var: FEISHU_IGNORE_AT_ALL=true
• YAML: feishu.ignore_at_all: true (bridged to the env var via the plugin's apply_yaml_config_fn hook; env wins when both are set)
• Default: false — behavior is unchanged for every existing user

When enabled, the @_all short-circuit in _mentions_self() is skipped and only explicit bot mentions trigger the bot (both the raw mentions[] path and the post/rich-text is_self ref path remain fully intact — an @_all ref never sets is_self, so the two paths don't interact).

Precedence chain: explicit env var → feishu.ignore_at_all YAML key → default false.

Naming note

The issue proposed FEISHU_IGNORE_MENTION_ALL / feishu.ignore_mention_all. This PR uses FEISHU_IGNORE_AT_ALL / feishu.ignore_at_all, the name that 3 of the 5 prior PRs for this issue converged on. Happy to rename if maintainers prefer.

Docs

Documented in English and zh-Hans: website/docs/user-guide/messaging/feishu.md (prose + table row), website/docs/reference/environment-variables.md, and both zh-Hans mirrors.

Test plan

• python -m pytest tests/gateway/test_feishu.py tests/gateway/test_feishu_bot_admission.py -q → 89 passed, 18 skipped
• Full Feishu suite (test_feishu.py, test_feishu_bot_admission.py, test_feishu_bot_auth_bypass.py, test_feishu_approval_buttons.py) → 104 passed, 18 skipped
• New tests cover: settings wiring (unset/false/true, extra-config override, env-wins-over-extra), _mentions_self gating (all-only gated when enabled, explicit bot mention still triggers when enabled), admission-level rejection/admission, YAML→env bridge (bridge set, env wins, key absent leaves env untouched), and _to_boolean edge pins ("TRUE"/"1" → False)
• git diff --check clean

Notes

Open question: the read path for require_mention in _load_settings uses the same extra.get(..., os.getenv(...)) ordering that makes extra-config override the env var (contradicting the apply_yaml_config_fn docstring "Env vars take precedence over YAML"). This PR fixes the ordering for the new key only, following the narrowest-patch approach — whether require_mention (and other keys using the same pattern) should be fixed too is a maintainer call.

[alt-glitch]

This was generated by AI during triage.

Duplicate of #60910: both use the same opt-in ignore_at_all configuration to gate Feishu's @_all self-mention path. #60910 is the earlier open implementation.

[DavidMetcalfe]

@alt-glitch — thanks for the triage cross-link. Adding context for the maintainers, since the label understates the differences:

• feat(feishu): add ignore_at_all config to opt out of @everyone triggering the bot #60910 (opened July 8) has had no commits in 7+ weeks, and its maintainer review (teknium1, July 10) identified that the documented feishu.ignore_at_all YAML path was not actually wired — _apply_yaml_config() only handled allow_bots — with a docs-table gap alongside it. That feedback remains unaddressed.
• This PR is based on current main, wires both the FEISHU_IGNORE_AT_ALL env var and the feishu.ignore_at_all YAML bridge (with the load_gateway_config() integration test the review requested, plus unit coverage for both paths), and completes the documentation in both tables the review flagged.

Given that, this is closer to a superseding implementation than a duplicate — but that's a maintainer call, so leaving the label decision with them. @glow1128's approach preserved the same default behavior, and if they return, the branch is trivially salvageable.