refactor: simplify runtime config and remove deprecated shims

[LIU9293]

Summary

• remove deprecated runtime config compatibility paths and Supabase/cloud-only code paths that are no longer used
• flatten IM runtime exports to client entry points (Slack, Discord, Lark) and delete unnecessary runtime barrel files
• fix CI worktree branch collisions with a CI-only scoped worktree id, clean unused imports/dead code, and bump version to 0.1.12

Validation

• bunx tsc --noEmit --pretty false --noUnusedLocals --noUnusedParameters
• CI=true bun test