feat: 支持皮肤包就地更新与新建即传

- 新增皮肤包更新接口，覆盖内容保持文件名不变，避免 APP 配置的主题引用失效
- 上传新皮肤后自动为空主题目录的证书选中该皮肤
- 新建 APP 保存后不关弹窗并回填 upload_key，可直接上传皮肤

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/routers/config.py

@@ -316,7 +316,7 @@ async def create_app(app: dict):
         apps[new_id] = app
         config["apps"] = apps
         save_config(config)
-    return {"id": new_id, "message": "App 已创建"}
+    return {"id": new_id, "upload_key": app["upload_key"], "message": "App 已创建"}
 
 
 @router.put("/apps/{app_id}")
@@ -410,6 +410,33 @@ async def upload_skin(upload_key: str, file: UploadFile = File(...)):
     return {"message": "皮肤包上传成功", "name": file.filename}
 
 
+@router.put("/skins/{upload_key}/{skin_name}")
+async def replace_skin(upload_key: str, skin_name: str, file: UploadFile = File(...)):
+    """替换已有皮肤包内容，保持原文件名不变。
+
+    APP 配置的 theme 通过文件名（去掉 .zip）引用皮肤包，若上传新文件名会新增一个皮肤而非更新，
+    导致原引用失效。此接口就地覆盖指定皮肤，确保被引用的皮肤可以更新。
+    """
+    if not file.filename or not file.filename.lower().endswith(".zip"):
+        raise HTTPException(status_code=400, detail="仅支持 .zip 格式")
+
+    config = load_config()
+    app_id, _ = _find_app_by_upload_key(config, upload_key)
+    if not app_id:
+        raise HTTPException(status_code=404, detail="App 不存在")
+
+    app_skins_dir = SKINS_DIR / upload_key
+    skin_path = app_skins_dir / skin_name
+    if not skin_path.exists():
+        raise HTTPException(status_code=404, detail="皮肤包不存在")
+
+    content = await file.read()
+    with open(skin_path, "wb") as f:
+        f.write(content)
+
+    return {"message": "皮肤包已更新", "name": skin_name}
+
+
 @router.delete("/skins/{upload_key}/{skin_name}")
 async def delete_skin(upload_key: str, skin_name: str):
     """删除指定皮肤包"""

frontend/src/views/ConfigView.vue

@@ -519,6 +519,10 @@
               <div v-for="skin in appSkins" :key="skin.name" class="skin-item">
                 <span class="skin-name">{{ skin.name }}</span>
                 <span class="skin-size">{{ formatSize(skin.size) }}</span>
+                <label class="skin-update-btn" :class="{ disabled: skinUploading }" title="更新（保持文件名不变）">
+                  更新
+                  <input type="file" accept=".zip" @change="updateSkin(skin.name, $event)" :disabled="skinUploading" hidden>
+                </label>
                 <button class="btn-icon btn-danger-icon" @click="deleteSkin(skin.name)" title="删除">&times;</button>
               </div>
             </div>
@@ -880,6 +884,12 @@ const uploadSkin = async (event) => {
       throw new Error(err.detail || '上传失败')
     }
     await loadSkins()
+    // 若某证书的主题目录还是空的，自动选中刚上传的皮肤
+    const skinTheme = file.name.replace(/\.zip$/i, '')
+    const certs = appForm.value.certificates || {}
+    Object.keys(certs).forEach(certType => {
+      if (!certs[certType].theme) certs[certType].theme = skinTheme
+    })
     event.target.value = ''
   } catch (e) {
     alert('上传失败: ' + e.message)
@@ -888,6 +898,32 @@ const uploadSkin = async (event) => {
   }
 }
 
+const updateSkin = async (skinName, event) => {
+  const file = event.target.files[0]
+  if (!file) return
+  const uploadKey = appForm.value.upload_key
+  if (!uploadKey) { event.target.value = ''; return }
+  skinUploading.value = true
+  try {
+    const formData = new FormData()
+    formData.append('file', file)
+    const res = await authFetch(`/api/config/skins/${uploadKey}/${skinName}`, {
+      method: 'PUT',
+      body: formData,
+    })
+    if (!res.ok) {
+      const err = await res.json()
+      throw new Error(err.detail || '更新失败')
+    }
+    await loadSkins()
+  } catch (e) {
+    alert('更新失败: ' + e.message)
+  } finally {
+    event.target.value = ''
+    skinUploading.value = false
+  }
+}
+
 const deleteSkin = async (skinName) => {
   if (!confirm(`确定删除皮肤包 ${skinName}？`)) return
   const uploadKey = appForm.value.upload_key
@@ -948,9 +984,18 @@ const saveApp = async () => {
       const err = await res.json().catch(() => ({ detail: '保存失败' }))
       throw new Error(err.detail || '保存失败')
     }
-    showAppModal.value = false
     await loadData()
+    if (!editingAppId.value) {
+      // 新建成功：不关弹窗，转为编辑态并回填 upload_key，让皮肤包上传区立即可用
+      const data = await res.json().catch(() => ({}))
+      editingAppId.value = data.id || editingAppId.value
+      if (data.upload_key) appForm.value.upload_key = data.upload_key
+      await loadSkins()
+      alert('保存成功，现在可以上传皮肤包了')
+    } else {
+      showAppModal.value = false
       alert('保存成功')
+    }
   } catch (e) {
     alert('保存失败: ' + e.message)
   }
@@ -1160,6 +1205,9 @@ const formatJson = () => {
 .btn-icon { width: 24px; height: 24px; border: none; border-radius: 4px; cursor: pointer; font-size: 16px; line-height: 1; display: flex; align-items: center; justify-content: center; }
 .btn-danger-icon { background: #fff1f0; color: #ff4d4f; }
 .btn-danger-icon:hover { background: #ff4d4f; color: white; }
+.skin-update-btn { font-size: 12px; color: #1890ff; cursor: pointer; padding: 2px 8px; border: 1px solid #91d5ff; border-radius: 4px; background: #e6f7ff; line-height: 1.4; }
+.skin-update-btn:hover { background: #1890ff; color: white; }
+.skin-update-btn.disabled { opacity: 0.5; pointer-events: none; }
 .btn-outline { background: white; border: 1px solid #1890ff; color: #1890ff; cursor: pointer; padding: 6px 16px; border-radius: 6px; font-size: 13px; display: inline-block; }
 .btn-outline:hover { background: #e6f7ff; }
 .btn-outline.disabled { opacity: 0.5; cursor: not-allowed; }