Remove plan mode from merge-ready UI

static/js/slashCommands.js

@@ -1254,23 +1254,6 @@ async function _cmdWorkspace(args, ctx) {
   slashReply('Usage: <code>/workspace</code> · <code>set /path</code> · <code>clear</code> · <code>pick</code>');
   return true;
 }
-// Plan mode: drive the real toggle pill (#plan-toggle-btn) so its per-mode
-// persistence/UI logic runs. Only meaningful in agent mode.
-async function _cmdTogglePlan(args, ctx) {
-  const btn = document.getElementById('plan-toggle-btn');
-  const chk = document.getElementById('plan-toggle');
-  if (!btn || btn.style.display === 'none' || btn.offsetParent === null) {
-    slashReply('Plan mode is only available in agent mode — switch to Agent first.');
-    return true;
-  }
-  const cur = !!(chk && chk.checked);
-  const v = (args[0] || '').toLowerCase();
-  const target = v === 'on' ? true : v === 'off' ? false : !cur;
-  if (target !== cur) btn.click();
-  slashReply(`Plan mode: ${target ? 'on' : 'off'}`);
-  return true;
-}
-
 async function _cmdToggleShow(args, ctx) {
   const name = (args[0] || '').toLowerCase();
   const val = (args[1] || '').toLowerCase();
@@ -5782,13 +5765,6 @@ const COMMANDS = {
     noUserBubble: true,
     usage: '/workspace [set <path> | clear | pick]',
   },
-  plan: {
-    alias: [],
-    category: 'Quick toggles',
-    help: 'Toggle plan mode (agent)',
-    handler: _cmdTogglePlan,
-    usage: '/plan [on|off]',
-  },
   memory: {
     alias: ['m'],
     category: 'Memory',