Create a Figma that defines the frontend the the flow

### What should be done?

Design a Figma prototype for the Miden MultiSig frontend that captures the key functionalities and flow. The Figma should reflect Miden’s design language, while drawing UI inspiration from Safe and Squad.

### How should it be done?

- Review the flow and role definitions described [here](https://github.com/0xMiden/miden-base/issues/1574#issuecomment-3078569348).
- Use Miden’s visual identity as the base (colors, fonts, minimalism).
- Incorporate design patterns from Safe (https://safe.global/) and Squad (https://www.squad.so/) for familiarity and usability.

The Figma should cover UI and UX for the following core flows:

1. Member Management
- View current members and threshold (n/m).
- Add and remove members.

2. Fund Overview
- Show total funds and asset breakdown.

3. Transaction Management
- Initiate a new transaction.
- View transactions in queue awaiting approval.
- Approve transactions.

4. Wallet Connection
- Simple and clear wallet connection flow.
- If the wallet doesn't know the MultiSig yet, it should be able to import it

5. General
- Ensure the flow clearly shows role-based interactions (e.g., proposer vs. approver).
- Keep the interface simple, functional, and mobile-friendly.

### When is this task done?

- [ ] the Figma reflects all actions and possible screens
- [ ] all relevant stakeholders provided feedback, e.g. Miden team and designer, Safe team

### Additional context

Excalidraw sketch https://excalidraw.com/#json=S-3wuzZH_UjoZEaQw-4Gw,VYUxhbG6uO2HvJdtuJqAlA