Turned on :error_handling, :underspecs, and :unmatched_returns in
mix.exs dialyzer config. The 97 warnings this surfaced were fixed in
place rather than suppressed:
- unmatched_return (79): explicit discard with `_ = ...` for
fire-and-forget side effects (Process.cancel_timer, :ets.new,
send/2), and pattern-matched `:ok = ...` for control-plane
Phoenix.PubSub subscribe/unsubscribe/broadcast calls so a future
return-shape change fails loud.
- contract_supertype (18): tightened @spec arg and return types on
data_builder, historical_loader, url_params, packet_utils,
encoding_utils, aprs_symbol, weather_controller, packet_replay to
match each function's actual success typing.
No behavioural change. mix compile clean, 1008 tests pass, dialyzer
count is now 0.
Drop the pre-insert aprs_messages broadcast in Is.dispatch (subscribers
already get a richer payload via postgres:aprsme_packets after insert).
Switch PacketsLive.CallsignView to the per-callsign packets:<CS> topic
so it only receives relevant packets instead of filtering every one.
In PacketConsumer: reuse the received_at stamped in Is.dispatch instead
of calling DateTime.utc_now/0 per packet; drop the duplicate struct_to_map
pass (Is.dispatch already handled it); fold coordinate validation and
Geo.Point construction into set_lat_lon + create_location_geometry so
coords are normalized once; extract device_identifier from the already-
normalized attrs; pre-build the broadcast payload once (identifier pick,
lat/lon aliases, routing callsign) so the async broadcast task no longer
does Map.drop/Map.merge per packet.
Rewrite PacketSanitizer.sanitize_packet / sanitize_data_map with Map.new/2
instead of Enum.reduce + Map.put — one allocation per packet instead of N.
Also compute has_weather in Packet.changeset/2 so direct-changeset inserts
(tests, backfills) populate it the same way the GenStage pipeline does.
