fix(webhook): surface DM topic routing keys in cross-platform delivery metadata

[liuhao1024]

What does this PR do?

Surfaces direct_messages_topic_id and telegram_reply_to_message_id from deliver_extra into the cross-platform delivery metadata dict in the webhook adapter.

Related Issue

Fixes #33375

Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)

Changes Made

• See commit messages for detailed changes

How to Test

1. Run pytest tests/ -q — all tests should pass
2. Verify the specific scenario described above is resolved

Checklist

Code

• I've read the Contributing Guide
• My commit messages follow Conventional Commits (fix(scope):, feat(scope):, etc.)
• I searched for existing PRs to make sure this isn't a duplicate
• My PR contains only changes related to this fix/feature (no unrelated commits)
• I've run pytest tests/ -q and all tests pass
• I've added tests for my changes (required for bug fixes, strongly encouraged for features)
• I've tested on my platform: macOS 26.4.1

Documentation & Housekeeping

• I've updated relevant documentation (README, docs/, docstrings) — or N/A
• I've updated cli-config.yaml.example if I added/changed config keys — or N/A
• I've updated CONTRIBUTING.md or AGENTS.md if I changed architecture and workflows — or N/A
• I've considered cross-platform impact (Windows, macOS) per the compatibility guide — or N/A

Code Intelligence

• Analyzed: gateway/platforms/webhook.py:_deliver_cross_platform (callers: webhook route dispatch, cross-platform delivery handler)
• Blast radius: LOW — additive change; existing configs without the new keys are unaffected
• Related patterns: gateway/platforms/telegram.py:_thread_kwargs_for_send already handles direct_messages_topic_id as an opt-out from the reply anchor requirement; tools/send_message_tool.py has a similar gap tracked in Cron delivery to private DM topics broken after PR #22410 — send_message_tool.py missing three-mode routing #22773

Checklist

• Tests added (3 new test cases for DM topic routing key passthrough)
• All existing tests pass (6/6 in TestDeliverCrossPlatformThreadId)
• Backward compatible (existing deliver_extra configs without new keys are unaffected)
• No unrelated files changed

[alt-glitch]

Duplicate of #33396 — both fix the same webhook DM-topic routing key forwarding bug in gateway/platforms/webhook.py. #33396 is more thorough: it forwards 4 routing keys (vs 2 here), adds type annotations, and has broader test coverage (5 tests vs 3).

[liuhao1024]

Superseded by #33396 which covers the same fix more thoroughly — forwards 4 routing keys (vs 2 here), adds type annotations, and has broader test coverage (5 tests vs 3).

Closing this as a self-duplicate. The canonical PR is #33396.

[teknium1]

Thanks for isolating the webhook metadata path.

Problems

• The original #33375 anchor-error premise no longer follows current main: plugins/platforms/telegram/adapter.py:931-949 only enters the anchor-required DM fallback when telegram_dm_topic_reply_fallback is present, and gateway/platforms/webhook.py:1260-1266 does not provide that marker.
• The forwarding list at gateway/platforms/webhook.py:1026 is incomplete for the current adapter contract. plugins/platforms/telegram/adapter.py:943 consumes telegram_dm_topic_created_for_send, and :993-1005 consumes telegram_dm_topic_reply_fallback; neither can be configured through this patch. The discussion-linked #33396 included both keys.

Suggested changes

• Salvage this as four-key routing metadata passthrough with focused coverage for the two omitted keys.

Automated hermes-sweeper review.

[teknium1]

Please include telegram_dm_topic_created_for_send and telegram_dm_topic_reply_fallback here as well. The current Telegram adapter consumes those signals at plugins/platforms/telegram/adapter.py:943 and :993-1005; omitting them leaves two supported routing modes impossible to express through deliver_extra.