Feature request: remoteControl field in ~/.claude/sessions/<pid>.json (+ optional command IPC)

Description

~/.claude/sessions/<pid>.json is a great integration point: PID, sessionId, cwd, version, entrypoint. Two additions would let external tools cooperate with sessions without fragile workarounds:

1. remoteControl: boolean

There is currently no external trace of whether a session has Remote Control enabled. We verified (2026-08-09, v2.1.226):

• /remote-control on|off changes nothing in config files, session metadata, or transcripts;
• the relay connection cannot be distinguished from ordinary API traffic by address — it terminates at the same edge IPs as api.anthropic.com and uses either address family;
• after /remote-control off the connection lingers, so even socket inspection cannot see the off-toggle.

A remoteControl field in the session file (updated on toggle) would make the state observable. Our use case: agent-deck colors each session's key blue when it can be picked up from the phone — today that relies on a connection heuristic plus manual pinning.

2. (Optional) documented session IPC for slash commands

The session file already references a messagingSocketPath. A documented way to ask a session to run a user-visible command — /compact being the prime candidate — would let external tools trigger it without X11 keystroke injection, which requires an unlocked desktop and breaks on Wayland. The phone app notably has no manual compact either; a local IPC would enable both hardware controllers and future remote UIs.

Expected

• ~/.claude/sessions/<pid>.json gains remoteControl: true|false, updated when the user toggles it.
• (Stretch) a minimal, documented IPC verb to enqueue a slash command such as /compact.