BOLT-823: Investigate 2 silent Tesla vehicles in Amazon Argus prod (connection state check)

Parent: BOLT-823. Amazon Argus prod workspace has 2 Tesla vehicles silent since 2026-05-04 14-16 UTC while still DeviceOnWorkspace.connected=true. Targets: - deviceId cmm13sxue0x8zhv1qpfmy23vt (model-y, manufacturerDeviceId 3744408557411591, connectionId cmntfhtjx08de11qku6c08ifp) - deviceId cmlzqaxg50pkggo1qccn47y9f (model-3, manufacturerDeviceId 3744615115556289, connectionId cmnxlaxl000yhvtxa77qys3q6) Workspace: cmk4advf40088nn1qu15dh9q3 (Amazon Argus production). Plan: 1. Query connect domain Connection + latest LinkSessionResult for both connectionIds. Check OAuth grant/refresh token freshness. 2. If tokens are dead: investigate why connect scheduler did not catch it and flip connected=false. Possibly related to the customer.deleted/device.deleted subscription gap (MEMORY.md 2026-04-21). 3. If tokens are alive: look at adapters/oem tesla manufacturer polling/webhook path for those specific VINs; check Datadog for adapter errors around 2026-05-04 14-16 UTC scoped to Amazon Argus workspace or those manufacturerDeviceIds. 4. Report findings + recommended remediation back to Richie in Slack before shipping any fix. Waiting on Richie before starting — he asked whether to dig in now.