D1-E: confirmed agent timeline through Desktop Runtime Gateway

• Issue: #8673
• Parents: #8574, #8566
• Status: closed; historical checked-in issue source
• Depends on: closed #8672

Landed boundary

Desktop Runtime Gateway protocol v3 adds one schema-bounded query:

agent.timeline(runRef)

Electron main obtains the shared #8672 reader from its authenticated Sync host, opens exactly scope.agent_run.<runRef>, and returns content only after that scope is live. A successful result contains:

• exact requested/confirmed run ref;
• the server-projected agent_run.routeId as routeRef;
• bounded lifecycle state/timestamps and confirmed entity version;
• actual scope phase/cursor/pending count; and
• at most 500 ordered confirmed event refs, sequences, generic type/summary/ status, artifact refs, timestamps, and versions.

The route rule is now frozen: routeRef from confirmed server state is the only run↔thread/route attachment fact. Renderer code may not transform or guess it from runRef. This avoids silently merging canonical chat identity with the older agent-run route convention.

Non-live, missing, and read failure return typed body-free unavailable results. The schema cannot carry owner/objective/repository/runtime/backend, provider source, raw payload JSON, external callback refs, credentials, store/session/ transport objects, arbitrary IPC, or process authority. No preload method or IPC channel was added; the existing generic decoded gateway call is reused.

Evidence

The Runtime Gateway e2e round-trips the query/result through both schema boundaries, proves the server routeRef survives unchanged, verifies bounded confirmed run/event versions, rejects an invalid traversal-shaped run ref, and proves a catching-up/offline scope returns no content. Desktop host tests prove the shared reader exists only behind live authenticated Sync and disappears on denial.

Contract: openagents_desktop.seam.runtime_gateway_agent_timeline.v1.

Explicit residual

No runtime launch, visible timeline, canonical chat creation for the route, provider process stream, interrupt/resume, mobile UI, or live-account proof is claimed here. Those later leaves consume this closed query; they do not widen it or invent a second event model.