GetVersion metadata endpoint

[fbac]

Add GetVersion metadata endpoint to return server version information

The metadata API service now includes a GetVersion RPC method that returns the server's version as a string. The changes include:

• Add version field to Service struct in pkg/api/metadata/service.go and update constructor to accept version parameter
• Generate protobuf definitions and gRPC service code for GetVersionRequest and GetVersionResponse message types
• Update server initialization in pkg/server/server.go to pass cfg.ServerVersion to metadata service constructor
• Add mock implementations for testing the new GetVersion method
• Generate OpenAPI/Swagger documentation for the new /mls/v2/metadata/version POST endpoint

📍Where to Start

Start with the GetVersion method implementation in the Service struct in pkg/api/metadata/service.go.

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Macroscope summarized 46c2a48.

[graphite-app]

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[fbac]

This is just a convenient endpoint to have, giving us visibility on all the nodes in the network. Also, will help during migration.