[upstream-sync] Port upstream CLI 0.0.420 protocol changes (copilot-sdk PR #605)

[github-actions]

Summary

Ports protocol-level changes from upstream github/copilot-sdk PR #605 (CLI version bump to 0.0.420) into idiomatic Clojure spec updates.

Upstream Changes Ported

From upstream PR #605 (Update @github/copilot to 0.0.420), the generated protocol types changed in nodejs/src/generated/session-events.ts:

New event type

• :copilot/subagent.deselected — new event emitted when a subagent is deselected. Added to event-types var in copilot_sdk.clj and ::event-type spec in specs.clj.

New attachment type

• :github-reference — new variant in the user.request_submitted event's attachments array, representing a GitHub issue, PR, or discussion. Added ::github-reference-attachment spec with fields: number, title, reference-type ("issue"/"pr"/"discussion"), state, url.

New optional fields on event data specs

• interaction-id — optional string field added to: ::user.message-data, ::assistant.turn_start-data, ::assistant.message_delta-data, ::tool.execution_complete-data
• model — optional string field added to ::tool.execution_complete-data (model used for the execution)
• plugin-name / plugin-version — optional string fields added to ::skill.invoked-data

New spec

• ::assistant.turn_start-data — previously undocumented, now has a formal spec with turn-id (required) and interaction-id (optional)

Changes Skipped (not relevant to Clojure port)

• PR #603 — Python-specific change: stop() now raises ExceptionGroup instead of returning a list. Python idiom, not applicable.
• PR #601, #596, #592, #561 — Python-specific fixes/improvements. Skip.
• PR #604, #582, #595, #594, #593, #579 — CI/CD and dependency bumps. Skip.
• PR #600, #597, #566, #556, #529 — Documentation-only changes for other SDKs. Skip.
• PR #586 — Go client data race fixes. Skip.
• PR #541, #533, #543 — .NET/Go specific. Skip.
• vision/reasoningEffort optionality (rpc.ts) — Already handled: Clojure specs define these as boolean? (already optional).

Testing

• ✅ Documentation validation passed (bb --config /dev/null script/validate_docs.clj)
• ⚠️ Full test suite not runnable in this environment (network blocked, Maven Central unreachable)

Changes are purely additive spec updates (new optional fields, new event type, new attachment variant) with no behavioral logic changes. All existing functionality is preserved.

Files Changed

• src/github/copilot_sdk/specs.clj — Spec additions/updates
• src/github/copilot_sdk.clj — New event type in event-types
• doc/reference/API.md — Event reference table updated
• CHANGELOG.md — [Unreleased] section updated

Generated by Upstream Sync Agent

• expires on Mar 9, 2026, 2:08 PM UTC

[Copilot]

Pull request overview

Ports upstream Copilot CLI 0.0.420 protocol schema updates into the Clojure SDK by extending clojure.spec coverage and updating the public event reference.

Changes:

• Added :copilot/subagent.deselected to the public event-types and ::event-type spec.
• Added a new :github-reference attachment variant and expanded several event data specs with new optional fields (e.g., :interaction-id, :model, plugin metadata).
• Updated the API reference event table and the [Unreleased] changelog notes.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
src/github/copilot_sdk/specs.clj	Extends protocol/message/event specs with new attachment type, new event type, and new optional fields.
src/github/copilot_sdk.clj	Adds the new event type to the exported event-types constant.
doc/reference/API.md	Documents the new :copilot/subagent.deselected event in the event reference table.
CHANGELOG.md	Records the upstream-sync additions under [Unreleased].