Open universal search modal instantly via client-side JS

Replace phx-click server event with Fluxon.open_dialog for zero-latency
modal opening. The modal DOM is now always present (no :if conditional) so
it can be shown instantly; the server syncs state in the background.

Fix test selectors that now match the always-present modal form by scoping
to forms without phx-target (which the modal form always has).

test/music_library_web/live/online_store_template_live/index_test.exs

@@ -25,7 +25,7 @@ defmodule MusicLibraryWeb.OnlineStoreTemplateLive.IndexTest do
       assert has_element?(view, "p", "Bandcamp")
 
       view
-      |> form("form", query: "Amazon")
+      |> form("form:not([phx-target])", query: "Amazon")
       |> render_change()
 
       assert_patch(view, ~p"/online-store-templates?page=1&page_size=50&query=Amazon")

test/music_library_web/live/scrobble_live/index_test.exs

@@ -40,7 +40,7 @@ defmodule MusicLibraryWeb.ScrobbleLive.IndexTest do
     test "renders search page with form", %{conn: conn} do
       conn
       |> visit(~p"/scrobble")
-      |> assert_has("form[phx-submit='search']")
+      |> assert_has("form[phx-submit='search']:not([phx-target])")
     end
 
     test "shows connect Last.fm button when not authenticated", %{conn: conn} do
@@ -67,7 +67,7 @@ defmodule MusicLibraryWeb.ScrobbleLive.IndexTest do
       session
       |> unwrap(fn view ->
         view
-        |> form("form[phx-submit='search']", %{query: "marbles"})
+        |> form("form[phx-submit='search']:not([phx-target])", %{query: "marbles"})
         |> render_submit()
 
         render(view)
@@ -82,7 +82,7 @@ defmodule MusicLibraryWeb.ScrobbleLive.IndexTest do
       session
       |> unwrap(fn view ->
         view
-        |> form("form[phx-submit='search']", %{query: ""})
+        |> form("form[phx-submit='search']:not([phx-target])", %{query: ""})
         |> render_submit()
       end)
       |> refute_has("h3", "Release Groups")
@@ -108,7 +108,7 @@ defmodule MusicLibraryWeb.ScrobbleLive.IndexTest do
       session
       |> unwrap(fn view ->
         view
-        |> form("form[phx-submit='search']", %{query: "nonexistent"})
+        |> form("form[phx-submit='search']:not([phx-target])", %{query: "nonexistent"})
         |> render_submit()
 
         render(view)

test/music_library_web/live/scrobble_rules_live/index_test.exs

@@ -140,7 +140,7 @@ defmodule MusicLibraryWeb.ScrobbleRulesLiveTest do
       {:ok, index_live, _html} = live(conn, ~p"/scrobble-rules")
 
       index_live
-      |> form("form[phx-change='search']", query: scrobble_rule.match_value)
+      |> form("form[phx-change='search']:not([phx-target])", query: scrobble_rule.match_value)
       |> render_change()
 
       assert_patch(index_live)

test/music_library_web/live/scrobbled_tracks_live/index_test.exs

@@ -56,7 +56,7 @@ defmodule MusicLibraryWeb.ScrobbledTracksLiveTest do
       session
       |> unwrap(fn view ->
         view
-        |> form("form[phx-submit='search']", %{query: "Unique Track"})
+        |> form("form[phx-submit='search']:not([phx-target])", %{query: "Unique Track"})
         |> render_submit()
       end)
       |> assert_has("p", "Unique Track Title")

test/music_library_web/live/universal_search_live/index_test.exs

@@ -23,7 +23,7 @@ defmodule MusicLibraryWeb.UniversalSearchLive.IndexTest do
     test "modal is hidden by default", %{conn: conn} do
       conn
       |> visit(~p"/collection")
-      |> refute_has("#universal-search-root")
+      |> assert_has("#universal-search-root[hidden]")
     end
 
     test "modal opens when search button is clicked", %{conn: conn} do