Accessibility: "light mode" option

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Is your feature request related to a problem?

Some people (myself included) have difficulty reading white/bright text on a dark background. This is caused by a well-documented and understood phenomenon known as halation. This is made even more challenging when text is relatively small and close together, as is common in PoB. conference paper and online article for reference.

Describe the solution you'd like

I would like to have the option of setting the colorscheme used to "lightmode", such that text is presented as predominantly dark characters on a light background (ie, black on white). Coloured text may need to be adjusted accordingly.
In terms of the main skilltree window, I don't see this as such a problem as it is both 1) integral to PoE itself and 2) can be panned and zoomed to make it a non-issue. However, pop-up/out text from hovering over a node/item/skill suffers similarly.

Describe alternatives you've considered

I have explored manually setting the hex values for some backgrounds myself - however with limited success.
Alternatively in a worst-case, the entire display color could also be inverted to provide some relief, however this would have unintended implications on anything else displaying on that monitor.

Additional context

No response

Das Issue nennt keine Dateien, Tests oder Einstiegspunkte. Beginne damit zu ermitteln, wo die Farben der Anwendung sowie der Text für Hover- oder Pop-up-Elemente definiert sind, und bestimme dann, wie ein auswählbares helles Farbschema diese konsistent abdecken könnte. Als erledigt gilt die Aufgabe, wenn Benutzer den hellen Modus auswählen können und der betroffene Text in der gesamten beschriebenen UI lesbar bleibt.