fix(memory): add Bun.gc, stream cancellation, and unconsumed fetch drains (#3416)

* fix(memory): add Bun.gc, stream cancellation, and unconsumed fetch drains

* fix(memory): await reader.cancel() and use non-blocking Bun.gc

* fix(memory): update Bun.gc comment to match non-blocking call

* fix(memory): use response.body.cancel() instead of response.text() for drains

* fix(executor): flush TextDecoder after streaming loop for multi-byte chars

* fix(memory): use text() drain for SecureFetchResponse which lacks body property

* fix(chat): prevent premature isExecuting=false from killing chat stream

The onExecutionCompleted/Error/Cancelled callbacks were setting
isExecuting=false as soon as the server-side SSE stream completed.
For chat executions, this triggered a useEffect in chat.tsx that
cancelled the client-side stream reader before it finished consuming
buffered data — causing empty or partial chat responses.

Skip the isExecuting=false in these callbacks for chat executions
since the chat's own finally block handles cleanup after the stream
is fully consumed.

* fix(chat): remove useEffect anti-pattern that killed chat stream on state change

The effect reacted to isExecuting becoming false to clean up streams,
but this is an anti-pattern per React guidelines — using state changes
as a proxy for events. All cleanup cases are already handled by proper
event paths: stream done (processStreamingResponse), user cancel
(handleStopStreaming), component unmount (cleanup effect), and
abort/error (catch block).

* fix(servicenow): remove invalid string comparison on numeric offset param

* upgrade turborepo

package.json

@@ -42,7 +42,7 @@
     "glob": "13.0.0",
     "husky": "9.1.7",
     "lint-staged": "16.0.0",
-    "turbo": "2.8.12"
+    "turbo": "2.8.13"
   },
   "lint-staged": {
     "*.{js,jsx,ts,tsx,json,css,scss}": [