chore: use builtin proseimg over custom element

components/content/ProseImg.vue

@@ -1,5 +1,7 @@
 <script setup lang="ts">
-const props = defineProps<{ src: string }>();
+const props = withDefaults(defineProps<{ src: string; alt?: string }>(), {
+  alt: "",
+});
 
 const src = props.src;
 const imgSrc =
@@ -10,7 +12,7 @@ const imgSrc =
 
 <template>
   <figure class="flex flex-col items-center">
-    <img :src="imgSrc" class="drop-shadow-lg" />
-    <figcaption class="text-center m-0"><slot /></figcaption>
+    <img :src="imgSrc" class="drop-shadow-lg" :alt="alt" />
+    <figcaption class="text-center" v-if="alt">{{ alt }}</figcaption>
   </figure>
 </template>