Revert "feat(kanban): durable multi-profile collaboration board (#16081)" (#16098)

This reverts commit 15937a6b46.

gateway/run.py

@@ -3503,14 +3503,6 @@ class GatewayRunner:
             if _cmd_def_inner and _cmd_def_inner.name == "background":
                 return await self._handle_background_command(event)
 
-            # /kanban must bypass the guard. It writes to a profile-agnostic
-            # DB (kanban.db), not to the running agent's state. In fact
-            # /kanban unblock is often the only way to free a worker that
-            # has blocked waiting for a peer — letting that be dispatched
-            # mid-run is the whole point of the board.
-            if _cmd_def_inner and _cmd_def_inner.name == "kanban":
-                return await self._handle_kanban_command(event)
-
             # Session-level toggles that are safe to run mid-agent —
             # /yolo can unblock a pending approval prompt, /verbose cycles
             # the tool-progress display mode for the ongoing stream.
@@ -3735,9 +3727,6 @@ class GatewayRunner:
         if canonical == "personality":
             return await self._handle_personality_command(event)
 
-        if canonical == "kanban":
-            return await self._handle_kanban_command(event)
-
         if canonical == "retry":
             return await self._handle_retry_command(event)
         
@@ -5165,37 +5154,6 @@ class GatewayRunner:
 
         return "\n".join(lines)
 
-
-    async def _handle_kanban_command(self, event: MessageEvent) -> str:
-        """Handle /kanban — delegate to the shared kanban CLI.
-
-        Run the potentially-blocking DB work in a thread pool so the
-        gateway event loop stays responsive.  Read operations (list,
-        show, context, tail) are permitted while an agent is running;
-        mutations are allowed too because the board is profile-agnostic
-        and does not touch the running agent's state.
-        """
-        import asyncio
-        from hermes_cli.kanban import run_slash
-
-        text = (event.text or "").strip()
-        # Strip the leading "/kanban" (with or without slash), leaving args.
-        if text.startswith("/"):
-            text = text.lstrip("/")
-        if text.startswith("kanban"):
-            text = text[len("kanban"):].lstrip()
-
-        try:
-            output = await asyncio.to_thread(run_slash, text)
-        except Exception as exc:  # pragma: no cover - defensive
-            return f"⚠ kanban error: {exc}"
-
-        # Gateway messages have practical length caps; truncate long
-        # listings to keep the UX reasonable.
-        if len(output) > 3800:
-            output = output[:3800] + "\n… (truncated; use `hermes kanban …` in your terminal for full output)"
-        return output or "(no output)"
-
     async def _handle_status_command(self, event: MessageEvent) -> str:
         """Handle /status command."""
         source = event.source