fix: correct task scheduling and simplify agent internals

Fix queue cancellation, concurrency limits and worker status updates.

Use direct Explorer imports, split the Diagnoser loop into helpers and remove unused tool registration and prompt-builder code.

Correct model caching, endpoint selection and retry handling.

artemis/tools/object_detection_tool.py

@@ -33,7 +33,7 @@ from artemis.data_engine.trace import (
 )
 from artemis.drivers.base import BaseDeviceDriver
 from artemis.graph.state import State
-from artemis.tools.base import ArtemisTool, ToolCategory, ToolRegistry
+from artemis.tools.base import ArtemisTool, ToolCategory
 from artemis.tools.tool_wrapper import ToolWrapper
 from artemis.tools.types import CyFunctionDetector
 from artemis.utils.logger import get_logger
@@ -220,8 +220,6 @@ operator_object_detection = OperatorObjectDetectionTool()
 OperatorObjectDetection = OperatorObjectDetectionTool
 OperatorObjectDetectorTool = OperatorObjectDetectionTool
 
-ToolRegistry.register(object_detection)
-
 
 def get_object_detector_tool(ctx: ArtemisContext) -> BaseTool:
     """Exports object_detection as a LangChain BaseTool."""