Function extractTwitterCard

extractTwitterCard(input: DocumentInput): TwitterCardMetadata
Extract Twitter Card metadata from HTML.
Parameters
- input: DocumentInput
  Parsed HTML document or raw HTML string
Returns TwitterCardMetadata
Twitter Card metadata object
Remarks
Extracts Twitter Card metadata including card type, site/creator info, title/description, images, app cards, and player cards.
Example
```
// With parsed document (recommended for multiple extractions)
const doc = parseHTML(htmlString);
const twitter = extractTwitterCard(doc);

// Or directly with HTML string
const twitter = extractTwitterCard(htmlString);
```
- Defined in src/metadata/twitter-card/extract.ts:38