change images to use ids instead of hashes

shared/src/entities/image.entity.ts

@@ -1,10 +1,8 @@
 import { z } from 'zod';
-import { SHA256Regex } from '../util/common-regex';
 import { IsEntityID } from '../validators/entity-id.validator';
 
 export const EImageSchema = z.object({
-  id: IsEntityID().optional(),
-  hash: z.string().regex(SHA256Regex),
+  id: IsEntityID(),
   data: z.undefined(),
   mime: z.string(),
 });