feat(oauth/oidc): move token exchange from beta to GA (#11475)

# Which Problems Are Solved

This PR marks the OAuth2 Token Exchange as general available (GA).

# How the Problems Are Solved

- API:
- deprecated the feature toggle (to prevent breaking changes) in v2beta
and v2 API
- removed all related event logic and updated the projection interation
  - removed the toggle usage for token exchange
  - removed related translations
- Management Console:
  - removed the feature toggle and its translations
- Docs:
  - removed all beta labels and feature toggle notes

# Additional Changes

- removed unused `Errors.WebKey.FeatureDisabled` translations

# Additional Context

- closes #11114

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Co-authored-by: Marco A. <[email protected]>

console/src/assets/i18n/zh.json

@@ -1638,8 +1638,6 @@
     "FEATURES": {
       "LOGINDEFAULTORG": "登录默认组织",
       "LOGINDEFAULTORG_DESCRIPTION": "如果没有设置组织上下文，登录界面将使用默认组织的设置（而不是实例的设置）",
-      "OIDCTOKENEXCHANGE": "OIDC 令牌交换",
-      "OIDCTOKENEXCHANGE_DESCRIPTION": "启用 OIDC 令牌端点的实验性 urn:ietf:params:oauth:grant-type:token-exchange 授权类型。令牌交换可用于请求具有较少范围的令牌或模拟其他用户。请参阅安全策略以允许在实例上模拟。",
       "USERSCHEMA": "用户架构",
       "USERSCHEMA_DESCRIPTION": "用户架构允许管理用户的数据架构。如果启用此标志，您将可以使用新的 API 及其功能。",
       "ACTIONS": "操作",