Add new AudienceGroupType TRACKINGTAG_WEBTRAFFIC to Audience Group API (#118)

# Add `TRACKINGTAG_WEBTRAFFIC` to **AudienceGroupType** Enum

We have supported for the new audience‑group type
**`TRACKINGTAG_WEBTRAFFIC`** (Tracking Tag Webtraffic audience) to the
OpenAPI schema.

## Changes Made

* **Updated `AudienceGroupType` enumeration**

  * **New value**: `TRACKINGTAG_WEBTRAFFIC`
* **Description**: Audience groups generated from Tracking Tag
Webtraffic.

## Purpose

This update enables correct identification and handling of audience
groups built from Tracking Tag Webtraffric.

## Documents and Reference

- [Managing
Audience](https://developers.line.biz/en/reference/messaging-api/#manage-audience-group)
- [News](https://developers.line.biz/en/news/2026/01/21/tracking-tag/)

For more information, please refer to the links provided above.

Author: drumnaoto

manage-audience.yml

@@ -795,6 +795,7 @@ components:
         - RICHMENU_IMP
         - RICHMENU_CLICK
         - POP_AD_IMP
+        - TRACKINGTAG_WEBTRAFFIC
     AddAudienceToAudienceGroupRequest:
       externalDocs:
         url: https://developers.line.biz/en/reference/messaging-api/#update-upload-audience-group