Deprecate HanaDB, HanaTranslator and update example notebook to use new implementation (#30896)

- **Description:**  
This PR marks the `HanaDB` vector store (and related utilities) in
`langchain_community` as deprecated using the `@deprecated` annotation.
  - Set `since="0.1.0"` and `removal="1.0"`  
- Added a clear migration path and a link to the SAP-maintained
replacement in the
[`langchain_hana`](https://github.com/SAP/langchain-integration-for-sap-hana-cloud)
package.
Additionally, the example notebook has been updated to use the new
`HanaDB` class from `langchain_hana`, ensuring users follow the
recommended integration moving forward.

- **Issue:** None 

- **Dependencies:**  None

---------

Co-authored-by: Chester Curme <chester.curme@gmail.com>

libs/packages.yml

@@ -643,3 +643,10 @@ packages:
   repo: valyu-network/langchain-valyu
   downloads: 120
   downloads_updated_at: '2025-04-22T15:25:24.644345+00:00'
+- name: langchain-hana
+  path: .
+  repo: SAP/langchain-integration-for-sap-hana-cloud
+  name_title: SAP HANA
+  provider_page: sap
+  downloads: 315
+  downloads_updated_at: '2025-04-27T19:45:43.938924+00:00'