refactor: remove non-functional compact view button from devices page

Removed:
- Compact view toggle button from the header
- toggle_compact_mode event handler
- @compact_mode assign

The button was not connected to any actual functionality.

lib/towerops_web/live/device_live/index.ex

@@ -36,7 +36,6 @@ defmodule ToweropsWeb.DeviceLive.Index do
      |> assign(:sites_enabled, organization.use_sites)
      |> assign(:has_sites, sites != [])
      |> assign(:reorder_mode, false)
-     |> assign(:compact_mode, false)
      |> assign(:total_devices, length(devices))
      |> assign(:total_up, Enum.count(devices, &(&1.status == :up)))
      |> assign(:total_down, Enum.count(devices, &(&1.status == :down)))
@@ -176,11 +175,6 @@ defmodule ToweropsWeb.DeviceLive.Index do
     {:noreply, assign(socket, :reorder_mode, !socket.assigns.reorder_mode)}
   end
 
-  @impl true
-  def handle_event("toggle_compact_mode", _params, socket) do
-    {:noreply, assign(socket, :compact_mode, !socket.assigns.compact_mode)}
-  end
-
   @impl true
   def handle_event("reset_order", _params, socket) do
     organization_id = socket.assigns.current_scope.organization.id

lib/towerops_web/live/device_live/index.html.heex

@@ -94,17 +94,6 @@
           <.button type="button" phx-click="toggle_reorder_mode" title="Reorder devices and sites">
             <.icon name="hero-bars-arrow-up" class="h-4 w-4" />
           </.button>
-          <.button
-            type="button"
-            phx-click="toggle_compact_mode"
-            title={if @compact_mode, do: "Normal view", else: "Compact view"}
-            variant={if @compact_mode, do: "primary", else: nil}
-          >
-            <.icon
-              name={if @compact_mode, do: "hero-view-columns", else: "hero-table-cells"}
-              class="h-4 w-4"
-            />
-          </.button>
         <% end %>
       <% end %>
       <.button :if={!@sites_enabled || @has_sites} navigate={~p"/devices/new"} variant="primary">