fix(feishu): reply in same topic instead of creating new one in topic-mode groups

[zhing2006]

What does this PR do?

Fixes Feishu bot replies creating a new topic instead of replying within the existing topic in topic-mode groups (话题模式群).

Root cause: progress messages and streaming responses were sent via the Feishu create API (no reply_to parameter), which cannot target a specific topic. Only the reply API with reply_in_thread=true can send messages into an existing topic. Since reply_to was missing, the code fell through to the create branch in _send_raw_message(), causing every bot response to appear as a new topic.

Related Issue

Fixes #6969

Type of Change

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

Changes Made

• gateway/stream_consumer.py: Add optional reply_to parameter to GatewayStreamConsumer.__init__() and use it in _send_or_edit() when sending the first message chunk
• gateway/run.py: Pass reply_to=event_message_id in all 3 progress-message adapter.send() calls inside send_progress_messages(), and in the GatewayStreamConsumer constructor
• gateway/platforms/feishu.py: Add defensive root_id fallback for thread_id in _process_inbound_message() for forum-type chats (topic-mode groups where thread_id may be absent); add debug logging for thread context

How to Test

1. Create or use a Feishu group with topic mode enabled (话题模式)
2. Open an existing topic and @mention the bot
3. Verify the bot's reply appears inside the same topic, not as a new topic
4. Also verify normal (non-topic) group and DM replies still work correctly

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: Windows 11 Pro

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 or workflows — or N/A
• I've considered cross-platform impact (Windows, macOS) per the compatibility guide — or N/A
• I've updated tool descriptions/schemas if I changed tool behavior — or N/A

Screenshots / Logs

Before fix — _send_raw_message log showing reply_to=None:

[Feishu] _send_raw_message: reply_to=None reply_in_thread=True msg_type=text metadata={'thread_id': 'omt_1abbed20d40f1c9e'}

After fix — bot reply correctly appears within the same Feishu topic.

[zhing2006]

Hey, just wanted to check in, this fixes an issue I ran into where the bot keeps opening new topics in Feishu topic-mode groups instead of replying in the same thread. Tested it on my end and it's working. Would appreciate it if someone could approve the CI run when they get a moment. Let me know if anything needs changing!