Tell the system prompt not to write incomplete code (#28245)

Sometimes agents do this. I've had some success responding by telling it
not to do this, so trying out having it in the system prompt.

Release Notes:

- Adjusted the system prompt to avoid incomplete code generation.
bfe08e449fRichard Feldman committed on 4/8/2025, 12:59:52 AM· committed by GitHubparentdf3c7a7
1 file changedLine totals unavailable