feat(genai): Samples/thinking #4175

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@Guiners

The following contributors were found for this pull request:

✅ 1f76398 Author: @Guiners <50328216+Guiners@users.noreply.github.com>
✅ 2b62432 Author: <r***a@softserveinc.com>
✅ 6d3ba66 Co-Author: @gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
✅ ac8dd76 Author: @msampathkumar <sa****hm@google.com>
✅ 1cee316 Author: @gericdong <it****c@google.com>

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