* fix(server): create autonomous turns for spontaneous ACP session updates
When an ACP-based provider handles background-agent completion
notifications, the resulting spontaneous session/update messages have no
active foreground turn to attach to. Mirror the Claude provider's
autonomous-turn mechanism so these updates are recorded in Paseo's
timeline.
- Start an autonomous turn when a sessionUpdate arrives with no active
foreground turn
- Tag timeline events with the autonomous turn id
- Complete the autonomous turn after a timeout, or before a new
foreground turn starts
* Fix ACP autonomous event scoping
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Co-authored-by: zab <b13022010527@gmail.com>
Co-authored-by: Mohamed Boudra <boudra.moha@gmail.com>
