[Feat] Create a "Notes" panel for GRASS GIS Mapset with Markdown Support

[lindakarlovska]

Overview: It would be nice to improve the project management and reproducibility by documenting details about the content of the current mapset directly in the GUI. I can imagine the new panel, let's say the "Notes" panel or "Metadata" panel implemented as a Markdown editor and viewer where users can write notes on stored maps, the analyses performed, and other relevant metadata. The notes will be saved as a Markdown file within the mapset directory and continuously updated to reflect any changes. This could make it easier for users to keep track of important information related to their work.

Key features:

• A panel in the GRASS GIS GUI that includes a text editor for writing in Markdown format.
• A live preview window displaying the rendered Markdown as HTML.
• Existing notes should be loaded when opening a mapset.
• It should allow users to save the Markdown file manually.
• The file should be automatically updated when users modify the content in the Notes Panel.

Implementation The suggestion is to use the markdown2 library for converting Markdown to HTML and wx.html2 for displaying Markdown content in the panel. I have created locally a small simple example of such a panel, it could look e.g. something like:

Any comments and suggestions are welcome!