Add Avatar Component

[GODrums]

Description

Add an avatar component with Storybook page. Fixes #30

Key Changes / Features

• Uses NgOptimizedImage to optimize performance
• Supports manual and default fallbacks through an image placeholder
• Storybook story with random avatar images

Further Resources

• https://angular.dev/guide/image-optimization
• https://www.spartan.ng/components/avatar

Checklist

General

• [x] PR title is clear and descriptive
• [x] PR description explains the purpose and changes
• [x] Code follows project coding standards
• [x] Self-review of the code has been done
• [x] Changes have been tested locally
• [x] Screenshots have been attached (if applicable)

Client (if applicable)

• [x] UI changes look good on all screen sizes and browsers
• [x] User experience and accessibility have been tested
• [x] Added Storybook stories for new components
• [x] Components follow design system guidelines (if applicable)

Screenshots

[FelixTJDietrich]

Generally looks good :)