Writer ODText: Support Default font color

[MichaelPFrey]

Description

Writer ODText: Support Default font color. This is continuation of #2731 #2700

Fixes # (issue)

style:use-window-font-color

Setting a default font-color is only possible, when style:use-window-font-color is either not set or set to false.

To see the effect of style:use-window-font-color, see the attachments of kde/kword bug 231659.

The definition of this attribute can be found in the OpenDocument Standard, where the most relevant phrase for this discussion are:

The determination of light or dark color is implementation-defined.

...

false: the foreground color is specified by the fo:color attribute.

kword did not support this attribute kde/kword bug 231659

Status: RESOLVED UNMAINTAINED

The "KOffice" application suite is no longer maintained, and all tickets are now closed.

The support in Microsoft office can be described as "partial" for example:

2.1.632 Section 15.4.4, Window Font Color
This attribute is supported in core Word 2007.
This attribute is not supported on save for text in SmartArt and chart titles and labels.
This attribute is not supported in core Excel 2007.

Properly implementing use-window-font-color would be a task separate from allowing setting a default font color.

Setting use-window-font-color in ODText, but not Word is inconsistent.

Checklist:

• My CI is 🟢
• I have covered by unit tests my new code (check build/coverage for coverage report)
• I have updated the documentation to describe the changes
• I have updated the changelog

[coveralls]

coverage: 96.823%. remained the same
when pulling 4e9f4cf on MichaelPFrey:mfr-2025-01-30-odt-defaultFontColor
into 269a810 on PHPOffice:master.

[Progi1984]

Thanks @MichaelPFrey