feat(routing): add thread parent binding inheritance for Discord (#3892)

* feat(routing): add thread parent binding inheritance for Discord

When a Discord thread message doesn't match a direct peer binding,
now checks if the parent channel has a binding and uses that agent.

This enables multi-agent setups where threads inherit their parent
channel's agent binding automatically.

Changes:
- Add parentPeer parameter to ResolveAgentRouteInput
- Add binding.peer.parent match type
- Resolve thread parent early in Discord preflight
- Pass parentPeer to resolveAgentRoute for threads

Fixes thread routing in Discord multi-agent configurations where
threads were incorrectly routed to the default agent instead of
inheriting from their parent channel's binding.

* ci: trigger fresh macOS runners

* Discord: inherit thread bindings in reactions

* fix: add changelog for thread parent binding (#3892) (thanks @aerolalit)

---------

Co-authored-by: Lalit Singh <lalit@clawd.bot>
Co-authored-by: OSS Agent <oss-agent@clawdbot.ai>
Co-authored-by: Shadow <shadow@clawd.bot>

CHANGELOG.md

@@ -8,6 +8,7 @@ Docs: https://docs.openclaw.ai
 
 ### Fixes
 
+- Discord: inherit thread parent bindings when routing Discord messages. (#3892) Thanks @aerolalit.
 - Docs: update MiniMax OAuth setup commands; Extensions: use OpenClaw plugin SDK for MiniMax OAuth. (#5402) Thanks @Maosghoul.
 - Discord: resolve PluralKit proxied senders for allowlists and labels. (#5838) Thanks @thewilloftheshadow.
 - Telegram: restore draft streaming partials. (#5543) Thanks @obviyus.