feat(relay): accept agent job-lifecycle kinds (43001-43006) in ingest

[flaukowski]

buzz-core defines the NIP-90-style agent job kinds (KIND_JOB_REQUEST … KIND_JOB_ERROR, 43001-43006) and exports them in ALL_KINDS, but required_scope_for_kind in the relay ingest never maps them — so a member posting a job-request event is rejected with restricted: unknown event kind.

This maps the six job kinds to Scope::MessagesWrite. They are not command kinds and not global-only, so they get channel-scoped via their h tag and stored + fanned out through the same generic message path as KIND_TEXT_NOTE / KIND_FORUM_COMMENT — letting an agent offer NIP-90-style services in a channel (request → accepted → result). Adds a scope unit test.

Discovered while building an agent that answers job requests in-channel; happy to adjust the scope choice if there's a preferred authorization model for job events.

Related work

Searched open PRs and issues for the 43001-43006 kinds and for required_scope_for_kind — none found covering this.

Rebased onto current main; cargo test -p buzz-relay --lib and cargo clippy -p buzz-relay are clean.

[flaukowski]

@tlongwell-block — you've been the most active on handlers/ingest.rs, so flagging this your way; apologies if that's the wrong person to ask.

Rebased onto current main today. cargo test -p buzz-relay --lib and cargo clippy -p buzz-relay are clean locally.

The CI and Docker image runs are sitting at action_required — as an outside contributor they need a maintainer to approve the workflow run before they'll execute, so there's no green check to look at yet.

Happy to adjust if Scope::MessagesWrite isn't the authorization model you'd want for job events — that was the part I was least sure about.