Fix RAHasher prod build

[dangmai]

Description
^{Explain the changes or enhancements you are proposing with this pull request.}

The current prod Dockerfile does not build. It needs some alpine-specific fixes.

Checklist
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• I've tested the changes locally
• I've updated relevant comments
• I've assigned reviewers for this PR
• I've added unit tests that cover the changes

Screenshots (if applicable)

[Copilot]

Pull request overview

Fixes the production Docker image build by adjusting the RAHasher build stage for Alpine/musl compatibility.

Changes:

• Add bash to the RAHasher build stage dependencies.
• Patch upstream RALibretro sources during the Docker build to add missing system headers required on Alpine/musl.

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