feat: add storage quota limit for S3/R2 channels

- Add quota counter tracking (usedMB, fileCount) per channel
- Filter channels by quota threshold in fetchUploadConfig()
- Update quota on upload (endUpload) and delete
- Add /api/manage/quota API for stats and recalculation
- Fix null check in delete when file record not found
- Fix R2 channel name from hardcoded to actual channel.name

functions/api/manage/delete/[[path]].js

@@ -2,6 +2,7 @@ import { S3Client, DeleteObjectCommand } from "@aws-sdk/client-s3";
 import { purgeCFCache } from "../../../utils/purgeCache";
 import { removeFileFromIndex, batchRemoveFilesFromIndex } from "../../../utils/indexManager.js";
 import { getDatabase } from '../../../utils/databaseAdapter.js';
+import { updateQuotaCounter } from '../../../upload/uploadTools.js';
 
 // CORS 跨域响应头
 const corsHeaders = {
@@ -125,6 +126,12 @@ async function deleteFile(env, fileId, cdnUrl, url) {
         const db = getDatabase(env);
         const img = await db.getWithMetadata(fileId);
 
+        // 如果文件记录不存在，直接返回成功（幂等删除）
+        if (!img) {
+            console.warn(`File ${fileId} not found in database, skipping delete`);
+            return true;
+        }
+
         // 如果是R2渠道的图片，需要删除R2中对应的图片
         if (img.metadata?.Channel === 'CloudflareR2') {
             const R2DataBase = env.img_r2;
@@ -136,6 +143,11 @@ async function deleteFile(env, fileId, cdnUrl, url) {
             await deleteS3File(img);
         }
 
+        // 更新容量计数器（在删除记录之前）
+        if (img.metadata?.ChannelName && img.metadata?.FileSize) {
+            await updateQuotaCounter(env, img.metadata.ChannelName, img.metadata.FileSize, 'subtract');
+        }
+
         // 删除数据库中的记录
         await db.delete(fileId);