feat: prepare 2.2.0 with UI and execution fixes

Add dark theme, richer Markdown and readable plugin results.
Improve Android input evidence, response integrity and diagnostics.
Unify lifecycle, guidance receipts and evidence sources across clients.
Keep direct action dispatch without an added AI quota approval layer.
Align version metadata at 2.2.0 and bundle Helper 1.2.2.

Validation: 3063 backend tests before the version bump; 44 after.
Frontend: 317 tests and production build passed.

artemis/agents/object_detector/object_detector.py

@@ -24,6 +24,7 @@ import re
 from langchain_core.messages import HumanMessage, ToolMessage
 
 from artemis.llm.structured import ParseFailure, parse_structured
+from artemis.runtime.cancellation import CancellationReason
 from artemis.services.llm import get_llm
 from artemis.utils.logger import get_logger
 
@@ -152,7 +153,7 @@ async def _run_object_detection(
     done, pending = await asyncio.wait(tasks, timeout=global_timeout)
 
     for task in pending:
-        task.cancel()
+        task.cancel(CancellationReason.OUTER_TIMEOUT)
     if pending:
         await asyncio.gather(*pending, return_exceptions=True)