UI Cleanup (#4191)

## Problem solved

Short description of the bug fixed or feature added

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## PR-Codex overview
This PR updates the connect modal styles and adds support for wallet authentication in the authentication flow.

### Detailed summary
- Updated connect modal styles
- Added support for wallet authentication
- Modified styles for various UI components
- Added a new component for copying addresses
- Improved wallet image rendering based on wallet type

> The following files were skipped due to too many changes: `packages/thirdweb/src/wallets/custom/smart/image.ts`, `packages/thirdweb/src/react/web/ui/ConnectWallet/Details.tsx`

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Author: gregfromstl

.changeset/light-countries-smell.md

@@ -0,0 +1,5 @@
+---
+"thirdweb": minor
+---
+
+Updates connect modal styles

packages/thirdweb/src/react/core/design-system/index.ts

@@ -170,6 +170,7 @@ export const fontSize = {
 };
 
 export const spacing = {
+  "4xs": "2px",
   "3xs": "4px",
   xxs: "6px",
   xs: "8px",