feat(genai): Sample/textgen part2 #4161

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@Guiners

The following contributors were found for this pull request:

✅ ea5fb69 Author: @Guiners <50328216+Guiners@users.noreply.github.com>
✅ dea5998 Author: <r***a@softserveinc.com>
✅ 5664c95 Co-Author: <sam******mar@gmail.com>
✅ e41a282 Author: @msampathkumar <sa****hm@google.com>
✅ 458e571 Author: @gericdong <it****c@google.com>

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