Add deprecation warning for transactions history by address (#736)

* Clarify transactions by address description limits

* Add deprecation warning for transactions history by address

Author: caleighc

src/openapi/beta/transactions/history/by-address.yaml

@@ -1,6 +1,13 @@
 summary: Transactions By Wallet (Beta)
-description: >
-  Fetches all historical transactions (internal & external) for multiple wallet addresses and networks. Returns a list of transaction objects with metadata and log information. This endpoint will be supported on Ethereum, Solana, and 30+ EVM chains (Beta: currently limited to Ethereum and Base with a limit of 1 address)
+description: |
+  Fetches all historical transactions (internal & external) for multiple wallet addresses and networks. (Currently limited to Ethereum and Base with a limit of 1 address) Returns a list of transaction objects with metadata and log information.
+
+  <Warning title="To be deprecated">
+  Please use `alchemy_getAssetTransfers` instead.
+
+  While you can continue using this endpoint for now, it is scheduled for removal. The recommended approach is to migrate to `alchemy_getAssetTransfers`, which has coverage for more chains and provides more complete and consistent results.
+
+  </Warning>
 tags: ["Beta API Endpoints"]
 parameters:
   - $ref: "../../../portfolio/portfolio.yaml#/components/parameters/apiKey"