fix(desktop): make recovery notice non-blocking

[M4n5ter]

Summary

English

The previous-session recovery dialog ran before Runtime Host boot. Restarting while it was open therefore left another unclean-run record and could repeat the same blocking dialog indefinitely.

This change starts Desktop normally, then presents the retained evidence as a compact, localized Toast. The live Renderer acknowledges the notice once while the original bounded diagnostic evidence remains copyable for the rest of that process. Current-startup fatal errors remain native and blocking.

简体中文

原有的上次运行恢复弹窗会在 Runtime Host 启动前显示。在弹窗打开时再次重启会留下另一条未正常退出记录，导致同一个阻塞弹窗可能无限重复。

本改动让 Desktop 先正常启动，再用紧凑且本地化的 Toast 展示已保留的证据。可用 Renderer 只确认一次提示，同时原有的有界诊断证据在本次进程中仍可复制。当前启动本身发生 fatal error 时仍使用原生阻塞错误。

Fixes #3804

Verification

English

• npm run build
• npm run typecheck
• npm run lint
• npm run format:check
• Focused Desktop recovery, diagnostics, and native-dialog tests: 29 passed
• Real npm run dev flow on macOS: force-terminated one run, verified the next run opened before showing the localized Toast, verified the pending record was acknowledged, then quit normally and verified a further launch showed no stale notice

简体中文

• npm run build
• npm run typecheck
• npm run lint
• npm run format:check
• Desktop recovery、diagnostics 与 native-dialog 定向测试：29 项通过
• macOS 真实 npm run dev 流程：强制终止一次运行，验证下一次先进入 Desktop 再显示本地化 Toast、pending 记录被确认；随后正常退出并验证再次启动不会显示旧提示

AI use

• No generative tool made a substantive contribution
• Generative tooling made a substantive contribution

Tool(s) and scope: OpenAI Codex assisted with diagnosis, implementation, tests, and development-path UI validation under the contributor's direction.

Checklist

• Tests cover the change and fail without it
• Lint, format, typecheck and the affected suites pass locally

Does this PR entail a change in behavior?

• Yes — described under Summary above
• No