repl: Unify notebook cell creation (#54765)

Release Notes:

- N/A

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Co-authored-by: Kirill Bulatov <kirill@zed.dev>
ab69fc6d1eFinn Evers committed on 4/29/2026, 7:14:05 AM· committed by GitHubparentb381941
2 files changedLine totals unavailable