Cherry-picked from PR #13077 commits:
- 5500c7d8 fix(gateway): stream consumer first message drops thread context
- e84403b9 test(gateway): add regression tests for stream consumer thread routing
Fixes: Streaming first message drops thread/topic context in Feishu group
topics, Slack threads, Telegram forum topics. Adds initial_reply_to_id
ctor arg to GatewayStreamConsumer, threaded through _send_or_edit and
_send_new_chunk. Also fixes Feishu _send_raw_message fallback path
(reply -> create) to use receive_id_type='thread_id' so the new message
lands in the correct topic instead of the main channel.
Authored by hrygo via PR #13077 (re-attributed from the bot-authored
salvage commit on the original branch).
ff14666cdc