Two user-visible crashes in MapLive seen on prod pods today:
1. `:preload_forecast` handle_info timed out a Task.async_stream subtask
after 10 s and the `Enum.map(fn {:ok, h} -> h end)` match cascaded
the `:exit, :timeout` into the LiveView process, terminating the
session. Adds `on_timeout: :kill_task` and flat-maps only :ok
elements — a slow NFS forecast hour now drops from the preload
payload instead of killing the LV.
2. `LiveStash.stash/1` crashed with `** (ArgumentError) errors were
found at the given arguments: 2nd argument: not a valid match
specification` inside `:ets.select_replace/2` on OTP 28. The dep
(live_stash 0.2.0) has a latent bug against the tightened OTP 28
match-spec validator. Both call sites (MapLive.select_band,
SubmitLive.switch_tab) now route through a new
`MicrowavepropWeb.LiveStashGuard.stash/1` wrapper that rescues
ArgumentError, logs a warning, and returns the socket unchanged.
Stash is a convenience for reconnect state — failing it does not
need to kill the user's session.
Drop the guard module once the upstream match-spec fix lands.
Graham McIntire
d88bdd70a8