Raindrop details with square brackets in not showing everything

[davep]

I need to remember to escape anything that will be shown, as by default Textual will treat the content of a Label as Rich markup; the result being something like this:

Note how the title and excerpt in the details panel are empty.

The usual method of handling this is to set markup=False on the Label but this seems to have been broken in Textual 0.86: Textualize/textual#5468

Update the details panel code so that it uses rich.markup.escape, as a workaround.