feat(member): stream the overview with keyset infinite scroll instead of loading every member

lib/mv_web/components/core_components.ex

@@ -953,6 +953,11 @@ defmodule MvWeb.CoreComponents do
     doc:
       "when true, first header/body column gets sticky left positioning to keep selection controls visible"
 
+  attr :viewport_bottom, :any,
+    default: nil,
+    doc:
+      "optional phx-viewport-bottom event (string) rendered on the streamed tbody so the built-in InfiniteScroll hook appends the next page without shifting the scroll position; nil omits the binding"
+
   slot :col, required: true do
     attr :label, :string
     attr :class, :string
@@ -964,6 +969,10 @@ defmodule MvWeb.CoreComponents do
 
   slot :action, doc: "the slot for showing user actions in the last table column"
 
+  slot :footer,
+    doc:
+      "optional after-rows content rendered as a full-width row in a separate, non-streamed tbody. Combined with viewport_bottom it acts as the infinite-scroll sentinel (e.g. a loading indicator) that fires the load event and disappears once no more pages remain."
+
   def table(assigns) do
     assigns =
       with %{rows: %Phoenix.LiveView.LiveStream{}} <- assigns do
@@ -986,6 +995,15 @@ defmodule MvWeb.CoreComponents do
     assigns =
       assign(assigns, :first_row_click_col_idx, first_row_click_col_idx)
 
+    # Total column span for full-width footer rows (e.g. the infinite-scroll
+    # loading indicator): fixed columns + dynamic custom-field columns + the
+    # optional action column.
+    col_count =
+      length(assigns.col) + length(assigns[:dynamic_cols] || []) +
+        if assigns.action != [], do: 1, else: 0
+
+    assigns = assign(assigns, :col_count, col_count)
+
     ~H"""
     <div
       id={@row_click && "#{@id}-keyboard"}
@@ -1021,7 +1039,10 @@ defmodule MvWeb.CoreComponents do
             </th>
           </tr>
         </thead>
-        <tbody id={@id} phx-update={is_struct(@rows, Phoenix.LiveView.LiveStream) && "stream"}>
+        <tbody
+          id={@id}
+          phx-update={is_struct(@rows, Phoenix.LiveView.LiveStream) && "stream"}
+        >
           <tr
             :for={row <- @rows}
             id={@row_id && @row_id.(row)}
@@ -1126,6 +1147,21 @@ defmodule MvWeb.CoreComponents do
             </td>
           </tr>
         </tbody>
+        <%!-- After-rows footer in its own, non-streamed tbody so it stays put
+        outside the phx-update="stream" container. When viewport_bottom is set it
+        doubles as the infinite-scroll sentinel: rendered only while more pages
+        exist, so once the last page loads it disappears and stops firing. --%>
+        <tbody
+          :if={@footer != [] && @viewport_bottom}
+          id={"#{@id}-footer"}
+          phx-viewport-bottom={@viewport_bottom}
+        >
+          <tr>
+            <td colspan={@col_count}>
+              {render_slot(@footer)}
+            </td>
+          </tr>
+        </tbody>
       </table>
     </div>
     """