[NAVREDESIGN] Swap screen

### **Description**

Update design of `Swap` screen.

### **Technical Details**

- Convert screen to new design
- Update nav bar to include network + account switcher
- Screen should reflect switcher updates

### **Acceptance Criteria**

- TBD

### **References**

- Figma - https://www.figma.com/file/qcwJHEEw5qyNru5mbFf6Oq/Nav-Redesign-Breakdown?node-id=114%3A2302
- ETA - 4 days

Start with the linked Figma Nav Redesign Breakdown, focusing on the Swap screen design and the network and account switcher. Trace the existing Swap screen and navigation entry points, then verify that the screen matches the design and reflects both switcher updates; acceptance criteria are currently TBD.

Written by the indexing model from the issue text.