feat(google/cloud/agentregistry/v1): onboard a new library

[suztomo]

b/524670267

V=v0.20.0
API_PATH=google/cloud/agentregistry/v1
go run github.com/googleapis/librarian/cmd/librarian@${V} add "${API_PATH}"
go run github.com/googleapis/librarian/cmd/librarian@${V} generate google-cloud-agentregistry

This includes README.md.

I had to make additional commit to add the "long" in devDependencies in package.json (googleapis/librarian#6501).

[gemini-code-assist]

Code Review

This pull request registers and adds a new Node.js client library package, @google-cloud/agentregistry, which includes its Protocol Buffer definitions, auto-generated client code, configuration files, samples, and system tests. I have no feedback to provide as there are no review comments to evaluate.

[suztomo]

It failed in Node 24 unit test:

> @google-cloud/agentregistry@0.1.0 compile
> tsc -p . && cp -r protos build/ && minifyProtoJson

protos/protos.d.ts:16:23 - error TS2307: Cannot find module 'long' or its corresponding type declarations.

16 import Long = require("long");
                         ~~~~~~


Found 1 error in protos/protos.d.ts:16