Add launcher preferences and modular landing studio [skip ci]

panel/server/tests/api.rs

@@ -233,6 +233,7 @@ async fn landing_page_config_and_permissions() {
     assert_eq!(v["brand_name"], "SCOPENET");
     assert_eq!(v["enabled"], true);
     assert!(v["blocks"].as_array().unwrap().len() >= 5);
+    assert_eq!(v["theme"]["accent"], "#6d6af5");
 
     // 2. Unauthenticated user cannot modify landing config
     let (s, _) = t.call("PUT", "/api/admin/landing", None, Some(json!({"brand_name": "Hacked"}))).await;
@@ -243,10 +244,24 @@ async fn landing_page_config_and_permissions() {
     let mut updated = v.clone();
     updated["brand_name"] = json!("PixelCraft");
     updated["hero_title"] = json!("Welcome to PixelCraft");
+    updated["theme"]["accent"] = json!("#17bebb");
+    updated["blocks"].as_array_mut().unwrap().push(json!({
+        "id": "b_custom_text", "type": "text", "enabled": true, "title": "Our story",
+        "subtitle": "", "options": { "body": "Built by players." }
+    }));
     let (s, v2) = t.call("PUT", "/api/admin/landing", Some(&admin), Some(updated)).await;
     assert_eq!(s, StatusCode::OK);
     assert_eq!(v2["brand_name"], "PixelCraft");
     assert_eq!(v2["hero_title"], "Welcome to PixelCraft");
+    assert_eq!(v2["theme"]["accent"], "#17bebb");
+    assert_eq!(v2["blocks"].as_array().unwrap().last().unwrap()["type"], "text");
+
+    // Duplicate IDs would break drag ordering and keyed public rendering.
+    let mut duplicate = v2.clone();
+    let first = duplicate["blocks"][0].clone();
+    duplicate["blocks"].as_array_mut().unwrap().push(first);
+    let (s, _) = t.call("PUT", "/api/admin/landing", Some(&admin), Some(duplicate)).await;
+    assert_eq!(s, StatusCode::BAD_REQUEST);
 
     // 4. Public endpoint reflects the updated config
     let (s, v3) = t.call("GET", "/api/v1/landing", None, None).await;