F-24: No automatic recovery after a WiFi, orchestrator or JMRI outage #27

Severity: HIGH · Effort: Medium · Batch: 3 · Status: Code done in #21 (b35b84c), awaiting bench verification

Found in the second full review of the firmware. Recorded with the rest of the pass (F-19…F-44) in docs/REVIEW_REMEDIATION_PLAN_2.md, which is where its status is kept.

Description

• WiFi gives up after five immediate retries and stays FAILED for good. A router reboot takes
  longer than those retries, and nothing retries afterwards.
• The orchestrator login is attempted once at boot. With the layout on one switch, the host
  comes up after the ESP and the device sits at FAILED.
• JMRI auto-connect waits 30 s for WiFi and then exits without ever starting the reconnect task.

In each case the operator has no control until they fix it by hand in settings.

Plan

1. WiFiManager: after the fast retries, keep retrying with a capped backoff until the
   operator disconnects or forgets the network.
2. Orchestrator: a supervising task that retries login and socket with backoff until
   connected, and re-logs in (rather than relying on the WebSocket's cookie-reusing
   auto-reconnect) when the socket stays down.
3. JMRI: wait for WiFi indefinitely and keep reconnecting once settings exist — done by the
   single jmri_conn task F-34 introduces.

Files: WiFiManager.h/.cpp, AppController.h/.cpp, JmriConnectionController.cpp

Acceptance Criteria

• WiFiManager keeps retrying after the immediate retries (one-shot esp_timer, 5 s
  doubling to 60 s) until Disconnect or Forget, both of which the WiFi screen now offers
  while it is in FAILED.
• orch_connect supervises for the life of the app: waits for WiFi indefinitely, retries
  a failed login with backoff, logs in afresh after 30 s without a socket, retries a failed
  roster read. The config screen's Connect wakes it instead of connecting itself.
• jmri_conn waits for WiFi indefinitely (see F-34).
• Bench: power-cycle the router with the device running; it reconnects without a touch.
• Bench: boot the device before the orchestrator host; it connects when the host is up.
• Bench: same for JMRI.