langchain

380449a7 - core: fix Image prompt template hardcoded template format (#27495)

core: fix Image prompt template hardcoded template format (#27495) Fixes #27411 **Description:** Adds `template_format` to the `ImagePromptTemplate` class and updates passing in the `template_format` parameter from ChatPromptTemplate instead of the hardcoded "f-string". Also updated docs and typing related to `template_format` to be more up-to-date and specific. **Dependencies:** None **Add tests and docs**: Added unit tests to validate fix. Needed to update `test_chat` snapshot due to adding new attribute `template_format` in `ImagePromptTemplate`. --------- Co-authored-by: Vadym Barda <vadym@langchain.dev>