bug: Thread History - Focused thread should be preserved when switching back and forth between Jan Pages

[Van-QA]

Describe the bug
Focused thread should be preserved when switching back and forth between Jan Pages, currently, it's auto-focusing on the first thread regardless the previous selection of users

Steps to reproduce
Steps to reproduce the behavior:

1. Selected view any old thread
2. Visit another page and go back
3. Observe the focused thread

Expected behavior
The selected thread should remain unchanged when users re-visit the thread page

Screenshots

Environment details

• Operating System: MacOS
• Jan Version: latest nightly build
• Processor: Apple M2 Pro
• RAM: 16GB

Logs
If the cause of the error is not clear, kindly provide your usage logs:

• tail -n 50 ~/jan/logs/app.log if you are using the UI
• tail -n 50 ~/jan/logs/server.log if you are using the local api server
  Making sure to redact any private information.

Additional context
Add any other context or information that could be helpful in diagnosing the problem.

[namchuai]

Moving milestone to 0.4.6 since 0.4.5 has been released.

[Van-QA]

Tested and looking good on Jan v0.4.5-198 ✅