Why

Modal interactions currently default to the main Slack session. This can misroute submissions/closures when a modal was launched from a specific channel/thread context.

Dependency

• Depends on Slack: improve Block Kit interaction handling (foundation) #18180, feat(slack): capture Block Kit view_closed lifecycle events #18234, and feat(slack): use static_select for large slash arg menus #18242.
• If reviewing before dependencies merge, review tip commit: afe40ca42.

What This PR Adds

• In /Users/solvely/Projects/OpenClaw/src/slack/monitor/events/interactions.ts:
  • parse view.private_metadata safely when present
  • support metadata routing fields:
    • sessionKey (explicit override)
    • channelId + optional channelType (derive session via existing resolver)
  • apply routing to both view_submission and view_closed
  • include routed channel hints in emitted payload (routedChannelId, routedChannelType)

Behavior

• If metadata contains sessionKey, modal events route directly there.
• Else if metadata contains channelId, route via resolveSlackSystemEventSessionKey({ channelId, channelType }).
• Else retain existing fallback routing.
• Invalid/non-JSON metadata safely falls back without throwing.

Validation

• pnpm test src/slack/monitor/events/interactions.test.ts
• pnpm check

Reviewer Focus

• src/slack/monitor/events/interactions.ts
• src/slack/monitor/events/interactions.test.ts