context-aware useConsistentTypeDefinitions

[eyy]

hello all!
i've enabled useConsistentTypeDefinitions in our codebase to enforce using type and not interface, but there a couple of places where we still need interfaces, namely when merging, e.g.

declare global {
  // biome-ignore lint/style/useConsistentTypeDefinitions: interface merging
  interface Window {
    dataLayer: unknown[];
  }
}

i suggest adding a new option to this rule, to allow interfaces inside declare blocks.