[Issue]: Refactor Vite image connection setup shows raw Tauri invoke error

[cha1latte]

Summary

On upstream/refactor, trying to create an Image Generation connection in the plain Vite web shell without a remote runtime shows a raw Tauri IPC error. The user sees Cannot read properties of undefined (reading 'invoke') instead of guidance about needing the Tauri shell or Remote Runtime URL.

Expected behavior

The web shell should either create the connection through an available runtime, or show a clear setup error such as "Remote Runtime URL is not configured" / "This action requires the Tauri app shell."

Actual behavior

Clicking Create for an Image Generation connection shows a raw JavaScript/Tauri implementation error:

Cannot read properties of undefined (reading 'invoke')

Steps to reproduce

1. Check out upstream/refactor at commit 507e64ac.
2. Run the Vite app.
3. Do not configure Remote Runtime URL.
4. Open Connections.
5. Click Add Connection.
6. Enter a name.
7. Select Image Generation.
8. Click Create.

Marinara Engine version

upstream/refactor commit 507e64ac

Install type

Source

OS + version

Windows, exact version not specified

Browser or app shell

Vite web shell in Chromium/Playwright

Screenshots or video

Logs

User-facing toast:

Cannot read properties of undefined (reading 'invoke')

Additional context

Likely owner/component: src/shared/api/tauri-client.ts runtime detection/error normalization and connection creation via storage API.

This blocks fresh browser/remote setup before users can configure image generation.

Template check

• I provided the required summary, behavior, reproduction, and environment details.
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