[Feature]: Adjust font colour based on background colour

[snigehere]

Requirements

• I have updated Mushroom to the latest available version
• I did a search to see if there is a similar issue or if a pull request is open.

Is your feature request related to a problem?

The font on the cards is always black text - when this is layered on a black background the font is not readable.

Describe the solution you'd like

Auto adjust the font colour based on the colour set in the pattern ... eg our wast bins are black and so I wanted a black background to the pattern but we can read the font - either date on a standard card or days to go on an icon card

Describe alternatives you've considered

No response

Additional context

No response