fix: prevent stale status overwrite after final update

[LIU9293]

Summary

• prevent a race where an in-flight progress tick can update the status message after completion and overwrite the just-published final result
• stop and drain progress updates before finalization, then freeze status updates on completion
• bump package version from 0.1.17 to 0.1.18

Testing

• bun test packages/core/test/request-runner.test.ts