reloadServer caught every error from both fallback mechanisms in bare
catch blocks, so a caller cancel or tool timeout was swallowed and fell
through to `proc.kill(); return "Restarted"` -- reporting a successful
restart while killing the server with no replacement.
- Propagate ToolAbortError/timeout from both the rust-analyzer request
and the didChangeConfiguration notification fallback.
- Gate the fallback on genuine method-not-found via isMethodNotFoundError
instead of any error.
- Replace the blind proc.kill with shutdownClientInstance: remove the
client from the registry by identity and await confirmed process exit,
surfacing a truthful teardown error when the process outlives the kill.
Fixes#6369
roboomp
eeb3fa6ace