Add support for Text fragment feature (#1545)

[thiru-appitap]

Text Fragment feature implementation pull request. The feature follows the published URL Fragment Text Directives specification (https://wicg.github.io/scroll-to-text-fragment/).

(base) lychee % lychee -vv --include-text-fragments https://developer.mozilla.org/en-US/docs/Web/URI/Fragment/Text_fragments
...
[DEBUG] tdirective: "text=From%20the%20foregoing%20remarks%20we%20may%20gather%20an%20idea%20of%20the%20importance
[DEBUG] status: Completed
[DEBUG] result: "From the foregoing remarks we may gather an idea of the importance"
[200] https://mdn.github.io/css-examples/target-text/index.html#:~:text=From%20the%20foregoing%20remarks%20we%20may%20gather%20an%20idea%20of%20the%20importance
[DEBUG] tdirective: "text=linked%20URL,-'s%20format"
[DEBUG] status: Completed
[DEBUG] result: "linked URL"
[DEBUG] tdirective: "text=Deprecated-,attributes,attribute"
[DEBUG] status: Completed
[DEBUG] result: "attributes charset Deprecated Hinted at the character encoding of the linked URL. Note:This attribute"
[200] https://developer.mozilla.org/en-US/docs/Web/HTML/Element/a#:~:text=linked%20URL,-'s%20format&text=Deprecated-,attributes,attribute
[DEBUG] tdirective: "text=downgrade:-,The%20Referer,be%20sent,-to%20origins"
[DEBUG] status: Completed
[DEBUG] result: "The Referer header will not be sent"
[200] https://developer.mozilla.org/en-US/docs/Web/HTML/Element/a#:~:text=downgrade:-,The%20Referer,be%20sent,-to%20origins
[DEBUG] tdirective: "text=linked%20URL,defining%20a%20value"
[DEBUG] status: Completed
[DEBUG] result: "linked URL as a download. Can be used with or without a filename value: Without a value, the browser will suggest a filename/extension, generated from various sources: The Content-Disposition HTTP header The final segment in the URL path The media type (from the Content-Type header, the start of a data: URL, or Blob.type for a blob: URL) filename: defining a value"
[200] https://developer.mozilla.org/en-US/docs/Web/HTML/Element/a#:~:text=linked%20URL,defining%20a%20value
...

If the fragment directive is not found, a TextDirectiveNotFound error will be returned.

Below changes are completed:

1. Fragment Directive parser uses fancy-regex

• this package was added as a dependency

2. a new flag, include-text-fragments is added to support the feature

• this is a deviation from the original feature request (which asked for using the text-fragments flag itself)

3. Fragment (Text) Directive feature is tested on LTR sites only
4. new UrlExt trait is implemented to enhance Url's to support Fragment Directive
5. Support for multiple text fragment directives (for example, #:~:text=linked%20URL,-'s%20format&text=Deprecated-,attributes,attribute)
6. tests are added for validating the feature
7. cargo clippy & cargo tests were executed

[thiru-appitap]

I missed to run the clippy across the test modules - the related lint failure issues are now fixed and ready for review!