Prompt to create support bundle before Reload Window on SSH failure

Split out from coder/vscode-coder#955 point (4).

## Summary

Detect Remote-SSH failure conditions before users click VS Code's native "Reload Window" prompt, then offer to create a Coder support bundle while volatile state is still available.

## Proposed scope

* Watch the actual Remote-SSH extension log for known failure markers:
* `permanent error`
* `will give up now`
* `Unknown reconnection token`
* `socketFactory.connect() failed or timed out`
* `Time limit reached`
* `UnparsableOutput`
* Treat long process-loss/no-recovery windows as a failure signal without firing during normal reconnect cycles.
* Show a notification:
* `Coder: remote session failed and won't auto-reconnect. Capture diagnostics now?`
* Actions: `Create support bundle`, `Dismiss`
* Running `Create support bundle` should invoke the existing `coder.supportBundle` command.
* Avoid duplicate notifications in a single failing session.

## Notes

This is intentionally separate from coder/vscode-coder#955's support bundle collection changes because the current `SshProcessMonitor` discovers ports/PIDs/proxy-log paths but does not tail or classify log contents. This should be implemented as a lifecycle-safe watcher/detector rather than added opportunistically to bundle collection.

Generated by Coder Agents.