Add CMS module

Static content pages (CmsPage) manageable from a new Filament resource and
readable via a public API endpoint. Wired into the admin panel with its own
CmsPlugin and "CMS" navigation group.

app-modules/cms/src/Http/Controllers/CmsPageController.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace Modules\Cms\Http\Controllers;
+
+use Illuminate\Http\Resources\Json\AnonymousResourceCollection;
+use Illuminate\Routing\Controller;
+use Modules\Cms\Http\Resources\CmsPageResource;
+use Modules\Cms\Models\CmsPage;
+
+class CmsPageController extends Controller
+{
+    public function index(): AnonymousResourceCollection
+    {
+        return CmsPageResource::collection(
+            CmsPage::query()->where('is_active', true)->paginate()
+        );
+    }
+
+    public function show(string $page): CmsPageResource
+    {
+        $cmsPage = CmsPage::query()
+            ->where('page', $page)
+            ->where('is_active', true)
+            ->firstOrFail();
+
+        return new CmsPageResource($cmsPage);
+    }
+}