docs: clarify required discovery service type

[darkdi]

Summary

• mark type as required in the discover_remote_services input schema description
• list the three accepted values so schema-validation errors are self-explanatory

Addresses #322.

Testing

• go test ./internal/node -run TestHandleDiscoverRemoteServices -count=1
• gofmt -d internal/node/mcp_handlers.go

A full go test ./internal/node run was also attempted; an unrelated macOS-only test setup failure occurs because the generated Unix socket path is 119 bytes while the kernel limit is 103.

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[gemini-code-assist]

Code Review

This pull request updates the JSON schema description for the Type field in DiscoverRemoteServicesParams to clarify that it is required and lists the allowed values. The review feedback points out that a2a is not supported by the underlying protobuf definition and should be removed from the description.

[gemini-code-assist]

The jsonschema tag lists a2a as one of the accepted values (One of: mcp, inference, a2a.). However, the underlying ServiceType enum in api/sam.proto only defines SERVICE_TYPE_MCP and SERVICE_TYPE_INFERENCE. Passing a2a will fail during api.ParseServiceType(params.Type) and return an error. Please remove a2a from the description unless it is supported by the protobuf definition.

Suggested change

	Type string `json:"type" jsonschema:"Required. One of: mcp, inference, a2a."`
	Type string `json:"type" jsonschema:"Required. One of: mcp, inference."`

[aojea]

A2A will be added by @kaisoz soon

[darkdi]

CI note: the failing e2e-android job timed out in mobile_e2e.sh while waiting 15 seconds for the host-node /mcp endpoint (exit 124). The same failure occurred in run 33445421284 on another PR, and a subsequent run on that branch passed. This patch only changes a jsonschema description; the other 12 checks, including Go tests, lint, Bats, and mesh E2E, passed. I do not have repository permission to rerun the failed job. Could a maintainer rerun e2e-android after the CLA is signed?

[aojea]

please rebase to get the latest ci fixes and sign the cla, thanks

[darkdi]

Rebased onto main and force pushed. The commit also carries the address that is on my GitHub account now, it went out under an old one before. CLA is next on my list.

[darkdi]

@googlebot I signed it!