Add more information to <a> and <img> tags in HTML Backend

### Discussed in https://github.com/DS4SD/docling/discussions/992

^{Originally posted by **alex-james-bit** February 16, 2025}
It would be interesting to see a feature in HTML Backend which captures - "src" attribute value of tag and "href" attribute of tag and mention the link while parsing.
This will allow users to navigate to links if navigation is supported to those links.

I can explain with an example -
```
Click Here to go to Google

```
This kind of output will ensure proper coverage of related information -
```
[Click Here to go to Google] (https://www.google.com)
[Image Found] (https://images.google.com)
```