add image picker to page editor and fix thumbnail layout

Wire up image field in block settings with a modal picker that
browses the media library. Fix picker thumbnails collapsing to
14px by replacing overflow:hidden with overflow:clip on grid
items (hidden sets min-height:0 in grid context). Polish media
library mobile sheet with scrim overlay and tighter spacing.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

lib/berrypod_web/page_editor_hook.ex

@@ -34,6 +34,10 @@ defmodule BerrypodWeb.PageEditorHook do
       |> assign(:editor_live_region_message, nil)
       |> assign(:editor_current_path, nil)
       |> assign(:editor_sidebar_open, true)
+      |> assign(:editor_image_picker_block_id, nil)
+      |> assign(:editor_image_picker_field_key, nil)
+      |> assign(:editor_image_picker_images, [])
+      |> assign(:editor_image_picker_search, "")
       |> attach_hook(:editor_params, :handle_params, &handle_editor_params/3)
       |> attach_hook(:editor_events, :handle_event, &handle_editor_event/3)
       |> attach_hook(:editor_info, :handle_info, &handle_editor_info/2)
@@ -262,6 +266,79 @@ defmodule BerrypodWeb.PageEditorHook do
     {:halt, assign(socket, :editor_picker_filter, value)}
   end
 
+  # ── Image picker actions ───────────────────────────────────────
+
+  defp handle_editor_action(
+         "show_image_picker",
+         %{"block-id" => block_id, "field" => field_key},
+         socket
+       ) do
+    images = Berrypod.Media.list_images()
+
+    {:halt,
+     socket
+     |> assign(:editor_image_picker_block_id, block_id)
+     |> assign(:editor_image_picker_field_key, field_key)
+     |> assign(:editor_image_picker_images, images)
+     |> assign(:editor_image_picker_search, "")}
+  end
+
+  defp handle_editor_action("hide_image_picker", _params, socket) do
+    {:halt,
+     socket
+     |> assign(:editor_image_picker_block_id, nil)
+     |> assign(:editor_image_picker_field_key, nil)}
+  end
+
+  defp handle_editor_action("image_picker_search", %{"value" => value}, socket) do
+    {:halt, assign(socket, :editor_image_picker_search, value)}
+  end
+
+  defp handle_editor_action("pick_image", %{"image-id" => image_id}, socket) do
+    block_id = socket.assigns.editor_image_picker_block_id
+    field_key = socket.assigns.editor_image_picker_field_key
+
+    case BlockEditor.update_settings(socket.assigns.editing_blocks, block_id, %{
+           field_key => image_id
+         }) do
+      {:ok, new_blocks} ->
+        socket =
+          socket
+          |> assign(:editing_blocks, new_blocks)
+          |> assign(:editor_dirty, true)
+          |> assign(:editor_image_picker_block_id, nil)
+          |> assign(:editor_image_picker_field_key, nil)
+          |> reload_block_data(new_blocks)
+
+        {:halt, socket}
+
+      :noop ->
+        {:halt, socket}
+    end
+  end
+
+  defp handle_editor_action(
+         "clear_image",
+         %{"block-id" => block_id, "field" => field_key},
+         socket
+       ) do
+    case BlockEditor.update_settings(socket.assigns.editing_blocks, block_id, %{
+           field_key => ""
+         }) do
+      {:ok, new_blocks} ->
+        socket =
+          socket
+          |> assign(:editing_blocks, new_blocks)
+          |> assign(:editor_dirty, true)
+          |> reload_block_data(new_blocks)
+
+        {:halt, socket}
+
+      :noop ->
+        {:halt, socket}
+    end
+  end
+
   # ── Page actions ─────────────────────────────────────────────────
 
   defp handle_editor_action("save", _params, socket) do
@@ -325,6 +402,10 @@ defmodule BerrypodWeb.PageEditorHook do
     |> assign(:editor_allowed_blocks, allowed)
     |> assign(:editor_live_region_message, nil)
     |> assign(:editor_sidebar_open, true)
+    |> assign(:editor_image_picker_block_id, nil)
+    |> assign(:editor_image_picker_field_key, nil)
+    |> assign(:editor_image_picker_images, [])
+    |> assign(:editor_image_picker_search, "")
   end
 
   defp exit_edit_mode(socket) do
@@ -338,6 +419,10 @@ defmodule BerrypodWeb.PageEditorHook do
     |> assign(:editor_allowed_blocks, nil)
     |> assign(:editor_live_region_message, nil)
     |> assign(:editor_sidebar_open, true)
+    |> assign(:editor_image_picker_block_id, nil)
+    |> assign(:editor_image_picker_field_key, nil)
+    |> assign(:editor_image_picker_images, [])
+    |> assign(:editor_image_picker_search, "")
   end
 
   defp apply_mutation(socket, new_blocks, message, type) do