refactor: remove unused cross-agent-comms subsystem

Nothing used the cross-agent message system (send/recv/watch/status/discover/halt/resume over the inbox/from-agents/ file-IPC protocol). Every cross-project handoff goes through inbox-send instead. I removed the scripts, READMEs, workflow, tests, INDEX entry, the three startup.org wirings, and the legacy bin symlinks, then repointed helper-mode's escalation to inbox-send and noted the removal in the generic-agent-runtime spec.

1 files changed, 0 insertions, 134 deletions

diff --git a/.ai/scripts/cross-agent-comms/cross-agent-halt b/.ai/scripts/cross-agent-comms/cross-agent-halt
deleted file mode 100755
index df25115..0000000
--- a/.ai/scripts/cross-agent-comms/cross-agent-halt
+++ /dev/null
@@ -1,134 +0,0 @@
-#!/usr/bin/env python3
-"""Failsafe halt for cross-agent comms.
-
-See cross-agent-halt.md. Touches ~/.config/cross-agent-comms/HALT and stops
-the cross-agent-watch systemd user service. With --tailnet, propagates the
-HALT file to every peer in peers.toml via SSH; reports per-peer status with
-non-zero exit on partial halt.
-
-Does NOT pkill in-flight scripts — they detect HALT on next iteration and
-stop themselves.
-"""
-
-from __future__ import annotations
-
-import argparse
-import subprocess
-import sys
-import tomllib
-from pathlib import Path
-
-CONFIG_DIR = Path.home() / ".config" / "cross-agent-comms"
-HALT_FILE = CONFIG_DIR / "HALT"
-PEERS_TOML = CONFIG_DIR / "peers.toml"
-
-EXIT_OK = 0
-EXIT_PARTIAL = 1
-
-
-def err(msg: str) -> None:
-    print(msg, file=sys.stderr)
-
-
-def write_halt_file(reason: str) -> None:
-    CONFIG_DIR.mkdir(parents=True, exist_ok=True)
-    HALT_FILE.write_text((reason + "\n") if reason else "")
-
-
-def stop_watcher_service() -> None:
-    """Best-effort stop of the systemd watcher service. Failures are logged but not fatal."""
-    try:
-        subprocess.run(
-            ["systemctl", "--user", "stop", "cross-agent-watch.path"],
-            capture_output=True, text=True, timeout=5,
-        )
-    except (FileNotFoundError, subprocess.TimeoutExpired):
-        # Watcher service may not be installed — fine.
-        pass
-
-
-def load_peers() -> dict:
-    if not PEERS_TOML.exists():
-        return {}
-    try:
-        return tomllib.loads(PEERS_TOML.read_text())
-    except (tomllib.TOMLDecodeError, OSError) as e:
-        err(f"cannot parse peers.toml: {e}")
-        return {}
-
-
-def ssh_touch_halt(host: str, ssh_user: str | None, reason: str) -> tuple[bool, str]:
-    target = f"{ssh_user}@{host}" if ssh_user else host
-    # Build the remote command. Quote the reason carefully.
-    remote_cmd = (
-        f"mkdir -p ~/.config/cross-agent-comms && "
-        f"printf %s {_sh_quote(reason)} > ~/.config/cross-agent-comms/HALT"
-    )
-    try:
-        result = subprocess.run(
-            ["ssh", "-o", "ConnectTimeout=3", "-o", "BatchMode=yes", target, remote_cmd],
-            capture_output=True, text=True, timeout=10,
-        )
-    except (FileNotFoundError, subprocess.TimeoutExpired):
-        return False, "ssh unavailable or timed out"
-    if result.returncode == 0:
-        return True, "HALT file written"
-    return False, (result.stderr.strip().splitlines() or [f"exit {result.returncode}"])[-1]
-
-
-def _sh_quote(s: str) -> str:
-    return "'" + s.replace("'", "'\"'\"'") + "'"
-
-
-def main() -> int:
-    parser = argparse.ArgumentParser(description="Halt all cross-agent comms on this machine (and optionally tailnet).")
-    parser.add_argument("reason", nargs="?", default="", help="Optional human-readable reason")
-    parser.add_argument("--tailnet", action="store_true",
-                        help="Propagate HALT to every peer in peers.toml")
-    args = parser.parse_args()
-
-    # Local halt.
-    write_halt_file(args.reason)
-    stop_watcher_service()
-    print("Halting locally       ✓ (HALT file written)")
-
-    if not args.tailnet:
-        print()
-        print(f"Halt active. Remove {HALT_FILE} or run cross-agent-resume to clear.")
-        print("Agent polling will stop within ~5 min (one cadence cycle).")
-        return EXIT_OK
-
-    peers = load_peers().get("peers", {})
-    if not peers:
-        print()
-        print("No peers configured in peers.toml — local-only halt complete.")
-        return EXIT_OK
-
-    print()
-    successes = 1  # local already counted
-    failures = []
-    for name, cfg in sorted(peers.items()):
-        host = cfg.get("host", name)
-        ssh_user = cfg.get("ssh_user")
-        ok, detail = ssh_touch_halt(host, ssh_user, args.reason)
-        marker = "✓" if ok else "✗"
-        print(f"Halting {host:<28} {marker} ({detail})")
-        if ok:
-            successes += 1
-        else:
-            failures.append(f"{name} ({host}): {detail}")
-
-    print()
-    total = len(peers) + 1
-    if failures:
-        print(f"PARTIAL HALT: {successes}/{total} machines halted.")
-        for f in failures:
-            print(f"  - {f}")
-        print("Resolve the failures or manually halt each machine.")
-        return EXIT_PARTIAL
-    print(f"Halt active across {total} machine(s).")
-    return EXIT_OK
-
-
-if __name__ == "__main__":
-    sys.exit(main())