feat(multipart): Add multipart upload support with MultipartUploadManager and controller integration

ts/classes/context.ts

@@ -2,6 +2,7 @@ import * as plugins from '../plugins.js';
 import { S3Error } from './s3-error.js';
 import { createXml } from '../utils/xml.utils.js';
 import type { FilesystemStore } from './filesystem-store.js';
+import type { MultipartUploadManager } from './multipart-manager.js';
 import type { Readable } from 'stream';
 
 /**
@@ -14,6 +15,7 @@ export class S3Context {
   public params: Record<string, string> = {};
   public query: Record<string, string> = {};
   public store: FilesystemStore;
+  public multipart: MultipartUploadManager;
 
   private req: plugins.http.IncomingMessage;
   private res: plugins.http.ServerResponse;
@@ -23,11 +25,13 @@ export class S3Context {
   constructor(
     req: plugins.http.IncomingMessage,
     res: plugins.http.ServerResponse,
-    store: FilesystemStore
+    store: FilesystemStore,
+    multipart: MultipartUploadManager
   ) {
     this.req = req;
     this.res = res;
     this.store = store;
+    this.multipart = multipart;
     this.method = req.method || 'GET';
     this.headers = req.headers;