维护者确认: Codex 图像通道动态模型选型 (PR #2226) — pluginBase

## 触发类别
pluginBase — 改动触及插件基座 (cindy-brain)，影响全部已装插件

## PR 概述
作者 painfulChen 将 Codex 图像通道的 host 模型从硬编码 gpt-5.5 改为按账号模型清单动态选型:
- codexImageClient.ts: 核心图像请求逻辑
- codexImageAuthBinding.ts: 认证绑定
- codex-model-discovery.ts: 模型发现机制
- index.ts: 模块入口

**pluginBase 不看 diff 大小、不走 fallback、不因「bugfix/纯技术改动」豁免**——插件基座改动作用到全部存量安装。

## 改动文件
- `apps/desktop/src/main/cindy-brain/codexImageClient.ts`
- `apps/desktop/src/main/cindy-brain/codexImageAuthBinding.ts`
- `apps/desktop/src/main/cindy-brain/index.ts`
- `apps/desktop/src/main/maker-host/codex-model-discovery.ts`
- 相关测试

## 确认方式
- 同意: 在 PR 上 Approve
- 需修改: Request Changes，作者改完后重新 Approve 即放行

---
关联 PR:#2226(作者 @painfulChen);本 issue 由 review-pr 流程自动创建,用于先讨论该 PR 涉及的插件基座改动(影响全部已装插件),维护者确认后 PR 会恢复推进。

Review PR #2226 alongside apps/desktop/src/main/cindy-brain/codexImageClient.ts, codexImageAuthBinding.ts, and index.ts, plus apps/desktop/src/main/maker-host/codex-model-discovery.ts. Start by checking the related tests and verify that dynamic account-model selection is consistent across the plugin base. Done means approving the PR or requesting specific changes for the author to address.

Written by the indexing model from the issue text.