Add support for AI Masks via AI Connector

[Duecki1]

Description

This PR adds support for the RapidRaw AI Connector for masking. RapidRaw now supports high quality masking models running on the gpu via ComfyUI.

CyberTimon/RapidRAW-AI-Connector#8

The workflow uses custom nodes. (https://github.com/PozzettiAndrea/ComfyUI-SAM3)

If this PR gets merged, I would like to implement person selection via sapiens.

Why this PR?

• Better masking quality
• GPU Support
• Android can connect to PC/Server to use better masking
• And maybe its a feature you could implement into the cloud too

Type of Change

• New feature

Changes Made

• Offloaded mask generation (subject for now) to ComfyUI via a new /mask endpoint
• Added universal model support (e.g., SAM2/SAM3)
• Updated Rust backend
• Added connection status indicator to the Masks Panel
• Add fallback to CPU when no workflow exists

Screenshots/Videos

CPU Model:

GPU via ComfyUI:

Testing

• I have tested these changes locally and confirmed that they work as expected without issues

Checklist

• My code follows the project's code style
• I haven't added unnecessary AI-generated code comments
• My changes generate no new warnings or errors

AI Disclaimer:

Please state the involvement of AI in this PR:

• This PR is AI-generated but guided by a human
• This PR was handwritten with AI assistance (spell check, logic suggestions, error resolving)