docs: Add databricks-langchain package consolidation notice (#27703)

Thank you for contributing to LangChain!

Add notice of upcoming package consolidation of `langchain-databricks`
into `databricks-langchain`.

<img width="1047" alt="image"
src="https://github.com/user-attachments/assets/18eaa394-4e82-444b-85d5-7812be322674">


Additional guidelines:
- Make sure optional dependencies are imported within a function.
- Please do not add dependencies to pyproject.toml files (even optional
ones) unless they are required for unit tests.
- Most PRs should not touch more than one package.
- Changes should be backwards compatible.
- If you are adding something to community, do not re-import it in
langchain.

If no one reviews your PR within a few days, please @-mention one of
baskaryan, efriis, eyurtsev, ccurme, vbarda, hwchase17.

Signed-off-by: Prithvi Kannan <[email protected]>
Co-authored-by: Erick Friis <[email protected]>

docs/docs/integrations/providers/databricks.md

@@ -20,6 +20,18 @@ First-party Databricks integrations are available in the langchain-databricks pa
 pip install langchain-databricks
 ```
 
+🚧 Upcoming Package Consolidation Notice
+
+This package (`langchain-databricks`) will soon be consolidated into a new package: `databricks-langchain`. The new package will serve as the primary hub for all Databricks Langchain integrations.
+
+What’s Changing?
+In the coming months, `databricks-langchain` will include all features currently in `langchain-databricks`, as well as additional integrations to provide a unified experience for Databricks users.
+
+What You Need to Know
+For now, continue to use `langchain-databricks` as usual. When `databricks-langchain` is ready, we’ll provide clear migration instructions to make the transition seamless. During the transition period, `langchain-databricks` will remain operational, and updates will be shared here with timelines and guidance.
+
+Thank you for your support as we work toward an improved, streamlined experience!
+
 Chat Model
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