chore: 将前端移动到 client/ 目录，准备合并为单仓库

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

client/src/components/dashboard/MarkdownEditor.vue

@@ -0,0 +1,35 @@
+<template>
+  <MdEditor v-bind="props" v-model="modelValue" @upload-img="uploadImg" />
+</template>
+<script lang="ts" setup>
+import { MdEditor } from "md-editor-v3"
+//@ts-ignore
+import "md-editor-v3/lib/style.css"
+import { Helper } from "../../api"
+import { useMessage } from "naive-ui"
+
+const message = useMessage()
+
+const modelValue = defineModel<string>()
+
+const props = defineProps()
+
+const uploadImg = async (files: File[], callback: (urls: string[]) => void) => {
+  try {
+    const res = await Promise.all(
+      files.map(async (file) => {
+        const path = await Helper.upload(file)
+        if (!path) {
+          message.error("图片上传失败")
+          return ""
+        }
+        return path
+      }),
+    )
+    callback(res.filter((url) => url !== ""))
+  } catch (err) {
+    message.error("图片上传失败")
+    callback([])
+  }
+}
+</script>