feat(wysiwyg): 캔버스 키보드 nudge/마우스 드래그 + 8px 스냅 (M1 1차)

- Frame/Layer/Object 스키마(zod) 및 테스트
- 키보드 화살표 nudge 시 8px 스냅 적용
- 마우스 드래그 이동 시 8px 스냅 적용
- Canvas 컴포넌트 초기 버전 및 테스트 추가

lib/wysiwyg/schema.ts

@@ -0,0 +1,60 @@
+import { z } from 'zod'
+
+const colorHex = z.string().regex(/^#([0-9a-fA-F]{3}){1,2}$/)
+
+const baseObject = z.object({
+  id: z.string().min(1),
+  x: z.number(),
+  y: z.number(),
+  width: z.number().positive(),
+  height: z.number().positive(),
+  rotate: z.number(),
+  zIndex: z.number().int().nonnegative(),
+})
+
+const textObject = baseObject.extend({
+  type: z.literal('text'),
+  props: z.object({
+    text: z.string(),
+    fontSize: z.number().positive(),
+    color: colorHex,
+  }),
+})
+
+const imageObject = baseObject.extend({
+  type: z.literal('image'),
+  props: z.object({
+    src: z.string().min(1),
+    alt: z.string().optional().default(''),
+  }),
+})
+
+const buttonObject = baseObject.extend({
+  type: z.literal('button'),
+  props: z.object({
+    label: z.string().min(1),
+    href: z.string().optional().default(''),
+    color: colorHex.optional(),
+    background: colorHex.optional(),
+  }),
+})
+
+export const objectSchema = z.discriminatedUnion('type', [textObject, imageObject, buttonObject])
+export type WObject = z.infer<typeof objectSchema>
+
+export const layerSchema = z.object({
+  id: z.string().min(1),
+  name: z.string().min(1),
+  visible: z.boolean(),
+  locked: z.boolean(),
+  objects: z.array(objectSchema),
+})
+
+export const frameSchema = z.object({
+  id: z.string().min(1),
+  width: z.number().positive(),
+  height: z.number().positive(),
+  background: colorHex,
+  layers: z.array(layerSchema),
+})
+export type Frame = z.infer<typeof frameSchema>