v0.1.3

interflow v0.1.3

Highlights:
- Edge self-dial agent self-heals: a connection-level death of the edge's internal hub dial used to zombie the whole gateway (site-wide 502 until a manual process restart; the in-process poll watchdog died with the poll loop and the connection-death signal was dropped unused). The internal agent now runs the same supervised auto-reconnect path as every expose client — in-process rebuild and re-registration within seconds.
- SessionSlot tunnel facade: embedders (the edge listener) hold one AgentTunnel across session rebuilds; sends during a reconnect gap fail fast with a bounded, actionable error instead of hanging or black-holing.
- Recovery-stack hardening: bounded abort-on-timeout joins in the session wind-down (a stuck child can no longer park the supervisor forever); /poll and /stream/up request-establishment timeouts (15s default, request_establish_timeout_secs override) covering the no-response-headers hang form invisible to both the watchdog and the connection-death detector; outer edge health watch (--agent-recovery-timeout-secs, default 120s) exits for a systemd restart only when the supervisor itself goes silent or fails without retry — normal reconnect cycling never trips it.
- Observability: per-attempt "Agent connecting (attempt=N)" logs; interflow_agent_session_join_timeout_total and interflow_agent_tunnel_establish_timeout_total metrics.

Verified: cargo test --workspace green (10 new: session-slot facade e2e, strangled-request e2e red-verified, health-watch e2e, bounded-join unit); serial e2e 112 green; clippy/fmt clean.

(Repointed to include the CI flake fix for the new facade e2e — production code identical.)