agent: Add Burn Mode setting migrator (#31718)

Follow-up https://github.com/zed-industries/zed/pull/31470.

Release Notes:

- N/A
9cf6be2057Danilo Leal committed on 5/30/2025, 11:10:12 AM· committed by GitHubparent5462e19
3 files changedLine totals unavailable