Issue #1125: Allow markdown formatting in "Description"

[kuchtiak-ufal]

Now,

Based on the

MarkdownConfig = {
    enabled: false,
    mathjax: false,
  };

definition user can use the https://commonmark.org/ or for https://www.mathjax.org/ formatting in the description property.

Example:
Description Metadata text:

## Math Expression
___
* enabled: true
* mathjax: true
___
The [Demo](https://www.mathjax.org/#demo)

When $a \ne 0$, there are two solutions to $ax^2 + bx + c = 0$ and they are
$$x = {-b \pm \sqrt{b^2-4ac} \over 2a}.$$

Result:

[Copilot]

Pull Request Overview

This PR implements markdown formatting support for description metadata fields in DSpace items. Users can now enable markdown and MathJax formatting in description fields through configuration.

Key changes:

• Added configuration injection to access markdown settings
• Implemented conditional rendering between plain text and markdown formats
• Fixed trailing comma syntax error in configuration

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
src/config/default-app-config.ts	Fixed trailing comma syntax error in markdown configuration
src/app/item-page/simple/field-components/clarin-description-item-field/clarin-description-item-field.component.ts	Added configuration injection and conditional logic for markdown rendering
src/app/item-page/simple/field-components/clarin-description-item-field/clarin-description-item-field.component.html	Added conditional rendering with markdown pipe when enabled