feat: add admin env badge, quick post button, and harden plugin enable

Show local/prod in the Filament topbar, jump to create post in one click, tighten sidebar spacing, and stop Hello World from 500ing when its tables are missing.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/Feature/DemoPluginTest.php

@@ -67,4 +67,24 @@ class DemoPluginTest extends TestCase
             ->assertOk()
             ->assertSee('Hello World 演示页');
     }
+
+    public function test_hello_world_page_survives_missing_log_table(): void
+    {
+        \Illuminate\Support\Facades\Schema::dropIfExists('hello_world_logs');
+
+        $this->get('/hello-world')->assertOk()->assertSee('Hello World 演示页');
+    }
+
+    public function test_enable_hello_world_runs_plugin_migrations(): void
+    {
+        \Illuminate\Support\Facades\Schema::dropIfExists('hello_world_logs');
+        \Illuminate\Support\Facades\DB::table('migrations')
+            ->where('migration', 'like', '%hello_world_logs%')
+            ->delete();
+
+        app(PluginManager::class)->enable('demo.hello-world');
+
+        $this->assertTrue(\Illuminate\Support\Facades\Schema::hasTable('hello_world_logs'));
+        $this->assertTrue(app(PluginManager::class)->isEnabled('demo.hello-world'));
+    }
 }