add(scan): Add ClearResults and DeleteKeys gRPC methods

[arya2]

Motivation

We want to clear results and delete keys in zebra-scan via gRPC requests.

Closes #8235

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Solution

• Adds the gRPC methods to the proto definition
• Implements the methods on ScannerRPC to call the ScanService

Testing

These methods still need tests, but they're thin wrappers around scan service requests that do have tests.

Review

Anyone can review.

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Follow Up Work

• Add tests to zebra-grpc

[oxarbitrage]

Looks good to me but i think we might want tests. We can do all the grpc testing (including snapshots) for all grpc in a separated ticket or add tests here so the other calls can follow.

Can you make a manual test and post the output ? A manual test should be to start the server and run these calls, make sure they reply as expected.

[arya2]

Looks good to me but i think we might want tests. We can do all the grpc testing (including snapshots) for all grpc in a separated ticket or add tests here so the other calls can follow.

I'll open an issue for adding tests for the gRPC methods, I think it's okay to add them later since the RPC methods are thin wrappers around the scan service calls.

Can you make a manual test and post the output ? A manual test should be to start the server and run these calls, make sure they reply as expected.

Yep, I'll start the server from zebrad in a follow-up PR targeting this branch for the manual test.

[arya2]

Manual test of these methods:

~/github/zebra$ $HOME/go/bin/grpcurl -plaintext -import-path ./zebra-grpc/proto -proto zebra-grpc/proto/scanner.proto -d '{"keys": [""]}' '[::1]:50051' scanner.Scanner/ClearResults
{}
~/github/zebra$ $HOME/go/bin/grpcurl -plaintext -import-path ./zebra-grpc/proto -proto zebra-grpc/proto/scanner.proto -d '{"keys": [""]}' '[::1]:50051' scanner.Scanner/DeleteKeys
{}

It seems strange to have a successful response when the provided keys were not registered in the scanner, we may want to return an error in that case later.