Feature request: in-IDE netcheck

Coder provides a `coder netcheck` command in the CLI to check networking and report possible issues. It would be great to provide a similar feature that's accessible through the IDE extension, so users don't need to run a CLI command to perform these diagnostics. Ideally, the diagnostics would run automatically if the IDE has trouble connecting or maintaining a stable connection (or perhaps on launch or periodically, regardless of detected trouble).

This is the Jetbrains counterpart to https://github.com/coder/vscode-coder/issues/348.