[FEATURE] Settings - Default Model Selection Feature

[didhd]

Feature Description
This feature request proposes the ability to select different default models, in addition to Claude, in the Amazon Bedrock Client for Mac.

Proposed solution
Implement a feature in the settings menu of the Amazon Bedrock Client for Mac that allows users to select from multiple default models. This would include a dropdown menu or selection list where users can choose from a variety of models based on their preferences and requirements.