Add preventing url preview cards by surrounding a link in anglebrackets

[nushea]

Description

This PR implements preventing previews by surrounding a link in angle brackets, it hides the angle brackets in both the formatted_body and the regular body, and instead adds the links as skeletons to the bundled previews.

This PR also serves as scaffolding for implementing the actual bundled previews.

(example of the 4 usages)

This PR matches the features #552 but uses the new standard way instead of an ad hoc solution

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings

AI disclosure:

• Partially AI assisted (clarify which code was AI assisted and briefly explain what it does).
• Fully AI generated (explain what all the generated code does in moderate detail).

My will be sin eater will clear me of the sin of having implemented this.