docs(priorities): refresh planner queue

[asim]

Summary:

• Remove the closed website quickstart on-ramp item from the loop queue.
• Add the deterministic universe A2A reachability issue discovered by the latest live-provider scan.
• Keep Now-phase side-effect safety ahead of protocol depth and later observability work.

Assessment:

• Shipped: docs: connect quickstart to first agent path #3656 closed docs: connect quickstart next steps to the first-agent on-ramp #3648, so the quickstart next-step/on-ramp item is done and should leave the queue. Recent merges also added micro loop dogfooding and loop prompt/role support (feat(loop): go-micro runs on micro loop (dogfood its own tool) #3657, feat(cli): prompt-file-driven micro loop + coherence & release roles #3655).
• In flight: no open codex PRs; open codex issues are agent: make plan-delegate conformance avoid duplicate task side effects #3626, agent: make universe conformance send exactly one concierge notification #3633, agent: make universe A2A reachability check deterministic #3653, a2a: expose fallback_echo tool during streaming fallback conformance #3560, Propagate agent run cancellation and deadlines through model and tool calls #3544, Emit OpenTelemetry spans for agent run timelines #3525, and interop: AP2 (Agent Payments Protocol) support — mandate layer over A2A + x402 #3552.
• Ranking rationale: developer adoption remains the current goal, but the explicit quickstart adoption gap shipped. The highest remaining adoption risk is trust in the first 0→hero agent/workflow story: duplicate side effects, flaky live-provider conformance, and non-deterministic A2A probes.

Testing:

• go build ./...
• go test ./... (environment blocks loopback gRPC targets; failures in client/grpc and transport/grpc report "Loopback targets forbidden")
• golangci-lint run ./... (initial default timeout)
• golangci-lint run ./... --timeout 5m

Closes #3658