Support the `FORCE_COLOR` emerging standard in ConsoleUtils.EmitAnsiColorCodes

[baronfel]

dotnet watch is likely spawning child processes with input/output streams redirected - many of our CLI outputs across .NET use 'is the output redirected' as a heuristic for 'am I allowed to output ANSI/VT control codes'. This check is not robust enough to support cases like watch.

There's an emerging standard env var called FORCE_COLOR that could be used here - the biggest CLI libraries and many popular apps support its use. If the .NET console loggers supported this, then watch could provide this variable and color-based experiences (though not interactive-based experiences) could be preserved.

Originally posted by @baronfel in #52864

We already support NO_COLOR for disablement, but it would be great if we also supported this flag for forcing the use of colorized outputs.

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