Customisable colours based on selector matching

[OrionReed]

This PR adds:

• A new "Choose Selectors" option which lets you more dynamically set color based on CSS selectors
• The option to rotate the DOM with Alt+Drag (disabled by default) which lets you rotate freely around the whole DOM, useful when trying to select an element or when you want to keep your perspective fixed and do other things.
• Usage of Biome as a formatter for consistency
• A new build.js script that simplifies the previous, verbose build step
• Refactor of code to improve maintainability and compatibility with the single function Gist

The Selectors input takes a JSON array with objects in the following format:

{
  "selector": "input > *",
  "hue": 190
}