Network badge is not cleared when disconnecting from app

Steps to reproduce:

1. Connect to an app that makes network requests
2. Navigate to network screen
3. See request number count going up in badge
4. Disconnect from app

Expect: count badge disapears
Actual: count badge is still there

Start by reproducing the issue through the network screen: connect to an app making requests, observe the request-count badge, and disconnect. Trace where the network screen handles disconnection and badge state; done means the badge disappears after disconnecting, with coverage for this sequence if the project has relevant tests.

由索引模型根据 Issue 内容生成。