assistant2: Rename key context to `AgentPanel` (#27859)

This PR renames the key context for the Agent Panel from
"AssistantPanel2" to "AgentPanel".

Release Notes:

- N/A
e63df58adcMarshall Bowers committed on 4/1/2025, 4:42:31 PM· committed by GitHubparent0ad4656
3 files changedLine totals unavailable