assistant2: Allow adding directories as context that contain non-UTF8 files (#26135)

We would previously return an error if there was at least one non-UTF8
file. Now we just ignore them and only add text files. If no text files
are found we show an error.

Release Notes:

- N/A
a602c50a6cBennet Bo Fenner committed on 3/5/2025, 4:47:43 PM· committed by GitHubparent728c161
1 file changedLine totals unavailable