fix(maestro): persist auto_approve across daemon restarts

Structured sessions spawned with auto_approve lost the flag on daemon
restart because it lived only in the in-memory SessionRecord. Add it to
the Session struct (sidecar JSON) so recovery reads it back instead of
hardcoding false.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

crates/maestro-cli/src/sessions.rs

@@ -345,6 +345,7 @@ mod tests {
             blocked_work: None,
             last_focused_at: None,
             acp_session_id: None,
+            auto_approve: false,
         }
     }