Function diffText

diffText(
    sourceHtml: string,
    targetText: string,
    options?: HighlightOptions,
): DiffTextResult
Compare HTML source against plain text and highlight the differences.

Strips tags from sourceHtml to extract the visible text, performs a word-level diff against targetText, and returns highlighted HTML for both sides along with structured segment data.
Parameters
- sourceHtml: string
  HTML string whose visible text is compared.
- targetText: string
  Plain text to compare against.
- Optionaloptions: HighlightOptions
  Optional configuration for highlight tags and CSS classes.
Returns DiffTextResult
A DiffTextResult with highlighted HTML, extracted text, segments, and similarity.
Example
```
import { diffText } from "text-visual-diff";

const result = diffText(
  "<p>Hello <b>world</b></p>",
  "Hello earth",
);

// result.highlightedSource – source HTML with <mark> tags
// result.highlightedTarget – target text with <mark> tags
// result.extractedText     – "Hello world"
// result.segments           – structured diff info
// result.similarity         – 0.55 (6/11 chars match)
```
- Defined in src/index.ts:73