v0.3.0dev1

What's Changed

• Update unit tests to catch up with langchain-core by @eyurtsev in https://github.com/langchain-ai/langserve/pull/743
• upgrade to pydantic 2 by @eyurtsev in https://github.com/langchain-ai/langserve/pull/744
• migrate examples to pydantic 2 by @eyurtsev in https://github.com/langchain-ai/langserve/pull/745
• chat-playground: update to handle oneOf (resulted from pydantic upgrade) by @eyurtsev in https://github.com/langchain-ai/langserve/pull/746
• update default playground to handle oneOf type by @eyurtsev in https://github.com/langchain-ai/langserve/pull/747
• 0.3.0.dev1 release by @eyurtsev in https://github.com/langchain-ai/langserve/pull/748

Full Changelog: https://github.com/langchain-ai/langserve/compare/v0.2.3...v0.3.0dev1