Feature request: Maintain remote session through CLI upgrade

Summary

When upgrading the Claude Code CLI (npm install -g @anthropic-ai/claude-code@<version>), all active remote control sessions are terminated and must be manually re-established. For users running multi-agent overnight workflows with 6-8 active remote sessions, every CLI upgrade is a 5-10 minute workflow disruption to rebuild session state.

Current behavior

1. User runs claude --resume <session-id> --agent <name> --model <model> --permission-mode <mode> in each of 6-8 terminal windows
2. User upgrades CLI via npm
3. All existing remote sessions die
4. User must manually relaunch each window with the full resume command
5. Each agent has to re-read state files, rehydrate context, and resync

Requested behavior

Active remote sessions should either:

• Survive the CLI upgrade (ideal)
• Auto-reconnect after upgrade completes using cached session metadata
• At minimum: provide a single "reattach all sessions" command after upgrade

Impact

Multi-agent workflows become dependent on holding off upgrades, which means users stay on buggy versions longer. The friction of reattaching 6-8 sessions per upgrade is significant enough that known-broken CLI versions stay in production longer than they should.