Restructure demos to examples

[waynemwashuma]

Objective

Restructures the examples to be self-contained, and updates configuration files to reflect these changes.

Solution

The demo system was previously centralized within the demos/ directory with shared dependencies and a complex demo runner. This refactor:

1. Renames demos/ to examples/ for better naming consistency
2. Moves assets from demos/assets/ to root assets/ directory
3. Restructures each demo into standalone examples that initialize their own App instances
4. Creates a new example browsing system for navigation
5. Updates build configurations (lint, TypeScript, Vite) to point to the new examples/ directory
6. Removes the centralized demo runner and plugin system in favor of individual example files

This approach was taken because:

• It simplifies the example structure, making each example self-contained and easier to understand
• It removes complex demo selection logic and plugin registration boilerplate
• It aligns with common practices in other frameworks where examples are standalone
• It improves maintainability by decoupling examples from each other

Showcase

N/A

Migration guide

This is an internal change, does not affect the library functionality.

Checklist

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.