clan-app: simplified task function, moved them to a separate file

pkgs/clan-cli/clan_lib/api/tasks.py

@@ -1,15 +1,36 @@
+import logging
+import threading
+from dataclasses import dataclass
+
 from clan_lib.api import API
 
+log = logging.getLogger(__name__)
+
+
+@dataclass
+class WebThread:
+    thread: threading.Thread
+    stop_event: threading.Event
+
+
+BAKEND_THREADS: dict[str, WebThread] | None = None
+
 
 @API.register_abstract
 def cancel_task(task_id: str) -> None:
     """Cancel a task by its op_key."""
-    msg = "cancel_task() is not implemented"
-    raise NotImplementedError(msg)
+    assert BAKEND_THREADS is not None, "Backend threads not initialized"
+    future = BAKEND_THREADS.get(task_id)
+    if future:
+        future.stop_event.set()
+        log.debug(f"Task with id {task_id} has been cancelled.")
+    else:
+        msg = f"Task with id {task_id} not found."
+        raise ValueError(msg)
 
 
-@API.register_abstract
+@API.register
 def list_tasks() -> list[str]:
     """List all tasks."""
-    msg = "list_tasks() is not implemented"
-    raise NotImplementedError(msg)
+    assert BAKEND_THREADS is not None, "Backend threads not initialized"
+    return list(BAKEND_THREADS.keys())