feat: improve config UI (#69)

* add first concept

* completed configuration ui update

* add button for testing email configuration

* improve mobile layout

* add migration

* run formatter

* delete unnecessary modal

* remove unused comment

frontend/src/types/config.type.ts

@@ -4,11 +4,29 @@ type Config = {
   type: string;
 };
 
+export type UpdateConfig = {
+  key: string;
+  value: string;
+};
+
 export type AdminConfig = Config & {
   updatedAt: Date;
   secret: boolean;
   description: string;
   obscured: boolean;
+  category: string;
+};
+
+export type AdminConfigGroupedByCategory = {
+  [key: string]: [
+    Config & {
+      updatedAt: Date;
+      secret: boolean;
+      description: string;
+      obscured: boolean;
+      category: string;
+    }
+  ];
 };
 
 export default Config;