feat: GRPC Callback API migration for Non Inference

[indrajit96]

What does the PR do?

This PR migrates NON-Inference RPCs from Completion Queue based to Callback based

Checklist

• PR title reflects the change and is of format <commit_type>: <Title>
• Changes are described in the pull request.
• Related issues are referenced.
• Populated github labels field
• Added test plan and verified test passes.
• Verified that the PR passes existing CI.
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Commit Type:

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• build
• ci
• docs
• feat
• fix
• perf
• refactor
• revert
• style
• test

Related PRs:

triton-inference-server/common#132

Where should the reviewer start?

Implementation of virtual inference::GRPCInferenceServiceCallback::CallbackService*

Flow of the changes

Step 1 : Created New Service Classes
Step 2 : Modified HandlerBase Interface
Step 3 : Updated CommonHandler Class
Step 4 : Modified Server Class
Step 5 : Changed Service Registration
Step 6 : Implemented Callback Methods

Test plan:

New test added test_grpc_callbacks.sh.
Moving forward will test with existing GRPC tests

• CI Pipeline ID:

Caveats:

PR cannot merge directly, as we CANNOT change the service name (will break backward compatibilty for all existing grpc clients)

Background

TEP here
https://docs.google.com/document/d/1LyxivxW7fCL0g8ZG2qT8DU2AV4l0XqYZYDkxRzYH9hs/edit?tab=t.0

Related Issues: (use one of the action keywords Closes / Fixes / Resolves / Relates to)

• closes GitHub issue: #xxx