Extend gRPC API for server-side scripting

Summary

Add new protofile for SSS.

• Implement current REST functionality as discussed in caosdb-server#357 (closed)
• Create issues for future ideas
• Add auth token passing

Expected Behavior

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Actual Behavior

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Steps to Reproduce the Problem

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Specifications

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• Platform: Which operating system, which other relevant software versions?

Possible fixes

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