[toofff]

Hello 👋 , this is my first PR here. I haven't created an issue for this change, but if it's important for the process, please let me know, and I'll create an issue and leave this PR as a draft.

useClipboard().copy and CopyButton value now accept rich content, so formatted text and tables keep their formatting when pasted in Google Docs, Gmail or Slack, and stay clean plain text in a plain text editor.

type ClipboardValue = string | { text: string; html?: string };

copy(value: ClipboardValue | (() => ClipboardValue)): void;

<CopyButton value={() => ({ html: ref.current!.innerHTML, text: ref.current!.innerText })}>
  {({ copied, copy }) => ...}
</CopyButton>

• A string is copied with writeText, as before
• An object with html is copied with clipboard.write as both text/html and text/plain
• An object without html, or a browser without ClipboardItem / clipboard.write, falls back to writeText(text)
• A function is called at the moment of copying, which is useful when the value is read from the DOM
• clipboard.write is called synchronously in copy, which is required by Safari
• copied and error follow the result of the write, including the reset of copied on error from [@mantine/hooks] use-clipboard: Reset copied state on error #9310
• ClipboardValue and ClipboardRichValue types are exported from @mantine/hooks

Note: copy was typed as (value: any) => void, it is now typed with ClipboardValue. Runtime behavior for strings does not change, but TypeScript code passing a non-string value will need a String() conversion.

Tests: new use-clipboard tests (string, rich content, fallbacks, function value, errors, timeout) and CopyButton tests.

Docs: "Rich content" and "Copy value on click" sections on the use-clipboard page, "Rich content" section on the CopyButton page, new demos and Storybook stories.