feat: Add Dark Mode Support to Ionicons Website

[manubravo]

Describe Problem

Currently, the Ionicons website does not support dark mode. Many users prefer or rely on dark themes to reduce eye strain, especially in low-light environments or at night. Having only a light mode can make it harder for some users to navigate the site comfortably.

Describe Preferred Solution

• Implement a CSS-based dark mode.
• Add a toggle switch to enable or disable dark mode manually or automatically.
• Ensure Ionicons Web Components have proper contrast in dark mode.
• Match the dark mode experience with other Ionic ecosystem sites.

Describe Alternatives

No response

Additional Information

No response

[ionitron-bot]

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