refactor: error handling logic

- Introduce `UnError` class to unify error handling
- Replace existing error handling methods with `UnError` to encapsulate error information
- Optimize code structure to improve consistency and readability of error handling

packages/core/src/adapters/download.ts

@@ -1,6 +1,7 @@
 import statuses from "statuses-es";
 import type { UnCancelTokenListener } from "../core/UnCancelToken";
 import { UnCanceledError } from "../core/UnCanceledError";
+import { UnError } from "../core/UnError";
 import { settle } from "../core/settle";
 import type { UnConfig, UnData, UnResponse } from "../types";
 import { buildDownloadConfig } from "../utils";
@@ -63,11 +64,7 @@ export const downloadAdapter = <T = UnData, D = UnData>(
         };
       },
       fail: (err) => {
-        response = {
-          ...response,
-          errMsg: err?.errMsg ?? err?.errmsg ?? err?.msg ?? err?.message,
-          errno: err?.errno,
-        };
+        reject(new UnError(err.errMsg, UnError.ERR_NETWORK, config, task));
       },
       complete: () => {
         if (onHeadersReceived) {

packages/core/src/adapters/request.ts

@@ -1,6 +1,7 @@
 import statuses from "statuses-es";
 import type { UnCancelTokenListener } from "../core/UnCancelToken";
 import { UnCanceledError } from "../core/UnCanceledError";
+import { UnError } from "../core/UnError";
 import { settle } from "../core/settle";
 import type { UnConfig, UnData, UnResponse } from "../types";
 import { buildRequestConfig } from "../utils";
@@ -52,13 +53,7 @@ export const requestAdapter = <T = UnData, D = UnData>(
         };
       },
       fail: (err) => {
-        response = {
-          ...response,
-          // @ts-expect-error no types
-          errMsg: err?.errMsg ?? err?.errmsg ?? err?.msg ?? err?.message,
-          // @ts-expect-error no types
-          errno: err?.errno,
-        };
+        reject(new UnError(err.errMsg, UnError.ERR_NETWORK, config, task));
       },
       complete: () => {
         if (onHeadersReceived) {

packages/core/src/adapters/upload.ts

@@ -1,6 +1,7 @@
 import statuses from "statuses-es";
 import type { UnCancelTokenListener } from "../core/UnCancelToken";
 import { UnCanceledError } from "../core/UnCanceledError";
+import { UnError } from "../core/UnError";
 import { settle } from "../core/settle";
 import type { UnConfig, UnData, UnResponse } from "../types";
 import { buildUploadConfig } from "../utils";
@@ -55,13 +56,7 @@ export const uploadAdapter = <T = UnData, D = UnData>(config: UnConfig<T, D>) =>
         };
       },
       fail: (err) => {
-        response = {
-          ...response,
-          // @ts-expect-error no types
-          errMsg: err?.errMsg ?? err?.errmsg ?? err?.msg ?? err?.message,
-          // @ts-expect-error no types
-          errno: err?.errno,
-        };
+        reject(new UnError(err.errMsg, UnError.ERR_NETWORK, config, task));
       },
       complete: () => {
         if (onHeadersReceived) {