feat: support amazon bedrock deepseek-r1 model

[zhu-xiaowei]

Description

1. Add amazon bedrock deepseek-r1 model support
2. Support deepseek-r1 model price display in usage page
3. Update Settings page, only display the corresponding models in the dropdown list when filling in OpenAI and DeepSeek API keys.
4. Fix the issue for the first token is space

General Checklist

• The code changes have been fully tested
• Security oriented best practices and standards are followed (e.g. using input sanitization, principle of the least privilege, etc.)
• Documentation update for the change if required
• PR title conforms to conventional commit style
• If breaking change, documentation/changelog update with migration instructions

By submitting this pull request, I confirm that my contribution is made under the terms of the MIT-0 license.