[Bug] Session hook interrupts compaction process prematurely

Question

**Bug Description**
somehow compaction doesn't work correctly for me, the session hook start runs too soon and it interrupts the whole compaction process at just 1-2%, and compaction is interrupted (silent error, no visible user msg) and the session start hook runs and it doesn't finish. pls fix.

**Environment Info**
- Platform: darwin
- Terminal: Apple_Terminal
- Version: 2.1.179
- Feedback ID: c9ca82d0-c9f1-44b9-bd78-12c8d8e4929f

**Errors**
```json
[]
```