Design 토큰 추가 (#17)

* feat: 디자인 토큰 background, line 색상 추가

Author: Hys-Lee

app/tokens.css

@@ -99,6 +99,7 @@
   --color-background-primary: #5d5fef;
   --color-background-alternative: #ffffff;
   --color-background-disabled: #b1b8be;
+  --color-background-assistive: #e6e8ea;
   --color-status-negative: #ea3429;
   --color-status-positive: #228738;
   --spacing-gap-2: 0.125rem;
@@ -154,4 +155,6 @@
   --non-mapped-textCase-none: none;
   --non-mapped-textDecoration-none: none;
   --spacing-paragraphIndent-0: 0px;
-}
+  --color-line-normal: #cdd1d5;
+  --color-line-disabled: #8a949e;
+}

components/shared/Test.stories.tsx

@@ -27,6 +27,11 @@ type Story = StoryObj<typeof meta>;
 
 // 가장 기본적인 Primary 스토리 (필수 권장)
 export const Primary: Story = {
+  argTypes: {
+    children: {
+      control: "text",
+    },
+  },
   args: {
     // Primary 스토리에만 적용될 Props
     children: "123",