Heartbeats carry per-level counts, the most frequent log types (a stable hash of the message) and the newest id, no text. The node keeps its last 2048 lines; moshiro.logs.fetch lets the backend pull them. The log page pulls when it is open, and the backend pulls warnings and errors once a minute after a node reports an error.
Replace Probe with Agent across node runtime, Fleet contracts, backend state, API and storage. Report incoming sessions and outgoing link health through each Agent uplink, and retain directed link controls and retry.
Update protocol fixtures and end-to-end coverage for the unified model; accept requested cancellation during the Fleet timeout test cleanup.