维护者确认: fix(desktop): stop retrying invalid embedding models

## 维护者确认请求

PR [#2288](https://github.com/makecindy/cindy/pull/2288) 需要维护者确认。

**触发类别**: arch — 核心路径改动

**改动概述**: 修复无效 embedding 模型重试逻辑，涉及主流程路径。

### 确认方式
- 如果改动合理，请直接在 PR 上 **Approve**
- 如果需要修改，请提交 **Request Changes**，作者修改后重新 Approve 即可放行

### 维护者
@dashhuang @DavidShenXD @fmfsaisai @kirozeng @magiclizi @xdanger @zqchris

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关联 PR:#2288(作者 @yuaiccc);本 issue 由 review-pr 流程自动创建,用于先讨论该 PR 涉及的技术架构调整,维护者确认后 PR 会恢复推进。

Start by reviewing PR #2288 and the related discussion, since this issue was created to obtain maintainer confirmation for that change. Determine whether the invalid embedding model retry behavior is correct and whether the core-path architecture change is acceptable; completion is maintainer approval or requested revisions on the pull request.

Written by the indexing model from the issue text.