Browser UI for RPi or mobile (see details): message list, filters (municipality, priority), detail view (subject, content, issuer, kid), text sending plus queued attachments.

Direct read of inbox_valid.jsonl, text rendering plus signature badge. Thumbnails appear when available, no crypto and no full browser inside the device.

Layout

• List (chrono/priority order) and detail (subject, content, issuer, date, kid).
• Action area (reply, forward, mark urgent) on the web UI.

Send / receive

• Send: build payload, sign, drop into outbox (JSONL or local DB), status signed_local.
• Receive: verify plus anti-replay, drop into inbox_valid, error journal.

Types and attachments

• Types: msg_forum, msg_private, alert, vote.
• Thumbnails = low priority, full attachments buffered on a relay disk.

Buffer / storage

• Outbox/inbox folders, disk quotas, purge/rotation.
• Export/import by key/SD or bundle, "super buffers" for large files.

Priorities

• P0 SOS/911, P1 PS/Gov, P2 municipalities, P3 public.
• Sort by priority plus TTL; alerts may bypass attachments.

Functions per station

• ESP32: text/thumbnail display, short sending, SOS/ACK buttons.
• Station H (RPi): verify, buffer, serve local UI, relay to K/backhaul.
• PS (fire/police/hospital): priority reception, auto ACK, local dissemination.
• Gov: aggregation, archiving, official announcements.
• Station K (mayor): polls/vote, thematic delegation, alerts (hop radius), manage undelivered, priority queue for large files, shadow copies for MANET-only zones.