test: fix async-hydration timeout flake + type warning

- Bump render_async/2 timeout to 2_000ms across contact_live_test.
  Default 100ms races when the suite runs on a loaded box — ContactLive.
  Show fans out 8 hydration tasks at mount and sporadically missed the
  window even on a quiet DB.
- Telemetry metrics-shape assertion uses Enum.any?/1 instead of the
  `metrics != []` comparison Elixir 1.19's type system flags as a
  distinct-type comparison (the function's non-empty return type).

test/microwaveprop_web/live/contact_live_test.exs

@@ -383,7 +383,7 @@ defmodule MicrowavepropWeb.ContactLiveTest do
 
       {:ok, lv, _html} = live(conn, ~p"/contacts/#{contact.id}")
 
-      html = render_async(lv)
+      html = render_async(lv, 2_000)
       assert html =~ "Atmospheric Profile"
       assert html =~ "NARR"
       # Collapsed summary shows HPBL / PWAT / lat,lon from the injected NARR row.
@@ -441,7 +441,7 @@ defmodule MicrowavepropWeb.ContactLiveTest do
         |> Repo.insert()
 
       {:ok, lv, _html} = live(conn, ~p"/contacts/#{contact.id}")
-      html = render_async(lv)
+      html = render_async(lv, 2_000)
 
       assert html =~ "HRRR native"
       # 300 mb comes from the native profile — pressure-level data capped at 700.
@@ -719,7 +719,7 @@ defmodule MicrowavepropWeb.ContactLiveTest do
 
       {:ok, lv, _html} = live(conn, ~p"/contacts/#{contact.id}")
 
-      html = render_async(lv)
+      html = render_async(lv, 2_000)
       # Surface Observations section is present; actual rows may or may
       # not render depending on internal proximity/time filters. The
       # render pass itself exercises the with-data code path either way.
@@ -758,7 +758,7 @@ defmodule MicrowavepropWeb.ContactLiveTest do
 
       {:ok, lv, _html} = live(conn, ~p"/contacts/#{contact.id}")
 
-      html = render_async(lv)
+      html = render_async(lv, 2_000)
       assert html =~ "KFWD"
     end
 
@@ -915,7 +915,7 @@ defmodule MicrowavepropWeb.ContactLiveTest do
       contact = seed_fully_hydrated()
 
       {:ok, lv, _html} = live(conn, ~p"/contacts/#{contact.id}")
-      html = render_async(lv)
+      html = render_async(lv, 2_000)
 
       # Headers / enrichment labels visible when data is present.
       assert html =~ contact.station1
@@ -932,7 +932,7 @@ defmodule MicrowavepropWeb.ContactLiveTest do
       contact = seed_fully_hydrated()
 
       {:ok, lv, _html} = live(conn, ~p"/contacts/#{contact.id}")
-      _ = render_async(lv)
+      _ = render_async(lv, 2_000)
 
       # Simulate the TerrainProfileWorker broadcast — the listener
       # recomputes elevation_profile and propagation_analysis and
@@ -946,7 +946,7 @@ defmodule MicrowavepropWeb.ContactLiveTest do
       contact = seed_fully_hydrated()
 
       {:ok, lv, _html} = live(conn, ~p"/contacts/#{contact.id}")
-      _ = render_async(lv)
+      _ = render_async(lv, 2_000)
 
       send(lv.pid, {:terrain_ready, Ecto.UUID.generate()})
       assert Process.alive?(lv.pid)
@@ -956,7 +956,7 @@ defmodule MicrowavepropWeb.ContactLiveTest do
       contact = seed_fully_hydrated()
 
       {:ok, lv, _html} = live(conn, ~p"/contacts/#{contact.id}")
-      _ = render_async(lv)
+      _ = render_async(lv, 2_000)
 
       send(lv.pid, {:sounding_fetched, %{contact_id: contact.id}})
       html = render(lv)
@@ -967,7 +967,7 @@ defmodule MicrowavepropWeb.ContactLiveTest do
       contact = seed_fully_hydrated()
 
       {:ok, lv, _html} = live(conn, ~p"/contacts/#{contact.id}")
-      _ = render_async(lv)
+      _ = render_async(lv, 2_000)
 
       send(lv.pid, {:sounding_fetched, %{contact_id: Ecto.UUID.generate()}})
       assert Process.alive?(lv.pid)

test/microwaveprop_web/telemetry_test.exs

@@ -9,7 +9,7 @@ defmodule MicrowavepropWeb.TelemetryTest do
       metrics = Telemetry.metrics()
 
       assert is_list(metrics)
-      assert metrics != []
+      assert Enum.any?(metrics)
 
       for m <- metrics do
         assert is_struct(m)