Fix sidebar overflow pickers and GJC status detection

[Cheol-H-Jeong]

Summary

• add separate closed/new sidebar overflow rows with ... N more controls
• add tmux popup pickers for all closed projects and all discoverable new projects
• persist and sort closed projects by most recently closed time
• recognize gjc as a coding agent in the watcher, while keeping the registry generic for all supported coding agents
• make GJC status detection distinguish active tool/subagent work from prompt-ready idle/done state
• ignore stale active markers from old GJC screen history before the latest forge banner
• treat GJC auto-handoff/context maintenance as non-development status when no real tool/subagent activity is present

Verification

node -c bin/nmux-linux
node -c bin/nmux-linux-sidebar
node --test test/mouse-binding.test.js
npm test
npm run check

Local result:

mouse-binding tests: 11 passed
full tests: 34 passed
npm run check: passed

Installed locally with:

./install.sh --no-deps --no-bashrc --no-claude-hooks --no-omx-patch

Live checks after watcher/sidebar refresh:

bid_monitor_kor       done
github_issue_solver   done

Persistent user/API config remained unchanged:

persistent_config_changed []

Notes

This PR is based on agent/issue-21-34 to avoid re-including the issue #21 pane-layout patch in this diff. It carries the local fixes for #20, #23, and #24 that were validated on the live tmux session.

[Cheol-H-Jeong]

Updated the PR with one more live-status fix discovered on nomadamas-code.

Problem:

• A prompt-ready GJC session can still burn ~60-80 CPU ticks for status redraw/token/heartbeat work.
• The generic CPU-first rule then briefly flipped an actually completed project back to running.
• Live watcher log example:

running→done gjc-prompt-ready
idle→running trigger=cpu 2640218:60~69

Fix:

• Keep generic CPU-first handling for all coding agents.
• But when a GJC prompt is visibly ready, require a stronger CPU signal before preserving running:

PROMPT_READY_CPU_ACTIVE_THRESHOLD = 180

This keeps real active work like the earlier onpremis_coding_agent case (~200-300+ ticks) as running, while suppressing prompt-ready heartbeat bursts.

Verification after update:

node -c bin/nmux-linux
node --test test/mouse-binding.test.js
npm test
npm run check

Result:

mouse-binding tests: 11 passed
full tests: 34 passed
npm run check: passed

Live install/check:

persistent_config_changed []
nomadamas-code done
bid_monitor_kor idle
github_issue_solver idle