feat(tmux): implement 2-hour inactivity session TTL reaper and prune command

bin/exec-constrained.py

@@ -729,6 +729,27 @@ def _tmux_kill_build(a):
     return [sys.executable, os.path.join(BIN_DIR, 'muse-tmux.py'), 'kill', a['session']]
 
 
+def _tmux_prune_validate(raw):
+    if not isinstance(raw, dict):
+        raise OpError('args must be an object')
+    allowed = {'ttl'}
+    for k in raw:
+        if k not in allowed:
+            raise OpError(f'unknown arg: {k}')
+    ttl = raw.get('ttl', 7200)
+    try:
+        ttl = int(ttl)
+        if ttl < 60:
+            ttl = 60
+    except Exception:
+        ttl = 7200
+    return {'ttl': ttl}
+
+
+def _tmux_prune_build(a):
+    return [sys.executable, os.path.join(BIN_DIR, 'muse-tmux.py'), 'prune', '--ttl', str(a['ttl'])]
+
+
 def _vars_list_validate(raw):
     if raw not in ({}, None):
         raise OpError('vars.list takes no required args')
@@ -1174,6 +1195,11 @@ OPS = {
         'timeout': 15, 'side_effecting': True,
         'desc': 'Kill a session on shared Muse tmux socket (/tmp/tmux-muse.sock)',
     },
+    'tmux.prune': {
+        'validate': _tmux_prune_validate, 'build': _tmux_prune_build,
+        'timeout': 15, 'side_effecting': True,
+        'desc': 'Reap stale unattached sessions inactive for >TTL (default 2h)',
+    },
     'exec.ping': {
         'validate': _health_validate,
         'build': lambda a: ['/bin/echo', 'PONG'],