Fixing issue on how options were being applied to the request.

[glecaros]

This pull request to sdk/js/packages/client/src/client.ts includes changes to improve the request preparation process and streamline the code. The most important changes include adding a new utility function for converting operation options to request parameters, refactoring the request preparation logic, and simplifying the request handling in the AIChatProtocolClient class.

Improvements to request preparation:

• sdk/js/packages/client/src/client.ts: Added operationOptionsToRequestParameters to the import statement.
• sdk/js/packages/client/src/client.ts: Refactored the prepareRequest method to use the new operationOptionsToRequestParameters utility function and simplified the logic for setting contentType and body properties. [1] [2] [3]

Simplification of request handling:

• sdk/js/packages/client/src/client.ts: Removed the options parameter from the post method calls in sendMessage and sendMessageAsStream methods to simplify the request handling. [1] [2]