chore: Update newer uv version in Dockerfile

[unixfox]

Summary

This updates the uv binary to 0.9.5 with support for python 3.12 as the python version provided in alpine (node:20-alpine).

This to allow the ability to use any python version through uv on aarch64 as commented here: #7984 (comment)

Change Type

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• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update
• Translation update

Testing

Launch Librechat with this new Docker image and configure an MCP server with uv.

Test Configuration:

   mcpServers:
     time:
        type: stdio
        command: uvx
        args:
          - mcp-server-time

Checklist

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• My code adheres to this project's style guidelines
• I have performed a self-review of my own code
• I have commented in any complex areas of my code
• I have made pertinent documentation changes
• My changes do not introduce new warnings
• I have written tests demonstrating that my changes are effective or that my feature works
• Local unit tests pass with my changes
• Any changes dependent on mine have been merged and published in downstream modules.
• A pull request for updating the documentation has been submitted.