fix(kanban): kanban_create inherits the spawning worker's task workspace (#37182)

When a dispatcher-spawned worker (HERMES_KANBAN_TASK set) calls
kanban_create without an explicit workspace, the new child now inherits
the worker's own running-task workspace_kind/workspace_path instead of
defaulting to scratch. A worker editing a dir:/worktree project that
spawns a follow-up child keeps it in that project.

Orchestrators (kanban toolset, no HERMES_KANBAN_TASK) and CLI/dashboard
callers still default to scratch. An explicit workspace arg always wins.

tools/kanban_tools.py

@@ -743,8 +743,18 @@ def _handle_create(args: dict, **kw) -> str:
     # CLI / dashboard paths and on legacy hosts that don't set the env.
     session_id = args.get("session_id") or os.environ.get("HERMES_SESSION_ID")
     priority = args.get("priority")
-    workspace_kind = args.get("workspace_kind") or "scratch"
+    # Resolve workspace. If the caller passed one explicitly, honor it.
+    # Otherwise, a dispatcher-spawned worker (HERMES_KANBAN_TASK set)
+    # inherits its own running task's workspace, so a worker editing a
+    # dir:/worktree project that spawns a follow-up child keeps the child
+    # in that project instead of a throwaway scratch dir. Orchestrators
+    # (kanban toolset, no HERMES_KANBAN_TASK) and CLI/dashboard callers
+    # fall back to scratch as before. Explicit None path stays None.
+    workspace_kind = args.get("workspace_kind")
     workspace_path = args.get("workspace_path")
+    _inherit_workspace = workspace_kind is None and workspace_path is None
+    if workspace_kind is None:
+        workspace_kind = "scratch"
     triage, bool_error = _parse_bool_arg(args, "triage")
     if bool_error:
         return tool_error(bool_error)
@@ -773,6 +783,15 @@ def _handle_create(args: dict, **kw) -> str:
     try:
         kb, conn = _connect(board=board)
         try:
+            # Inherit the spawning worker's own task workspace when the
+            # caller didn't specify one (see resolution note above).
+            if _inherit_workspace:
+                _self_tid = os.environ.get("HERMES_KANBAN_TASK")
+                if _self_tid:
+                    _self_task = kb.get_task(conn, _self_tid)
+                    if _self_task is not None and _self_task.workspace_kind:
+                        workspace_kind = _self_task.workspace_kind
+                        workspace_path = _self_task.workspace_path
             new_tid = kb.create_task(
                 conn,
                 title=str(title).strip(),