feat: add proto descriptor set and message name to introspect response

[AnthonyWadham]

TL;DR

Adds proto descriptor metadata to command introspection so clients can encode commands as protobuf without a separately distributed .proto file.

What changed?

Commands now use a dedicated commandReflector that falls back to Go field names (instead of msgpack tags) when generating their JSON schema, since proto field names align with Go names rather than msgpack tags.

During command registration, the proto descriptor is resolved from the return type of each command's ToProto() method via reflection — the method is never invoked, only its return type is inspected. The resolved protoreflect.MessageDescriptor is stored in a new commandProtoTypes map keyed by command name.

When Introspect is called, collectDescriptorSet walks all resolved descriptors, pulls in transitive file imports (deduplicated by path), and serializes the result as a google.protobuf.FileDescriptorSet into IntrospectResponse.proto_descriptor_set. Each command's TypeSchema also gains a proto_message_name field carrying the fully-qualified proto message name, so clients can look up the right message in the descriptor set. File ordering is deterministic (sorted by command name before walking) to produce byte-identical output across calls.

The proto definitions for IntrospectResponse and TypeSchema are updated accordingly, with generated code regenerated for Go, C#, and TypeScript.

The existing msgpack-based schema path for components and events is unchanged.

Why make this change?

Clients receiving command schemas from introspection need enough information to encode commands as protobuf on the wire without access to a compiled .proto descriptor at build time. Shipping the FileDescriptorSet alongside the fully-qualified message name in the introspection response allows clients to construct valid protobuf payloads — for example via protobufjs's Root.fromDescriptor — using only what the server advertises at runtime.

[AnthonyWadham]

• feat: add proto descriptor set and message name to introspect response #909 👈 (View in Graphite)
• main

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