feat: custom video button theme

[aeksandla]

No description provided.

[gravity-ui-bot]

Preview is ready.

[gravity-ui-bot]

Playwright Test Component is ready.

[aeksandla]

Copied from the original styles of the button. Replacing it with a mixin is a breaking change.

[aeksandla]

for test

{
  "theme": "custom",
  "colors": {
    "light": {
      "circleColor": "green",
      "circleHoverColor": "olive",
      "triangleColor": "yellow",
      "triangleHoverColor": "orange"
    }
  }
}