Experimental: add flatlaf LNF

[facchinm]

As suggested by #6153 (comment)

Highly experimental, only light theme activated.
If it runs well on HiDPI displays, it would make sense to add themes support

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[ArduinoBot]

✅ Build completed.

Please test this code using one of the following:

⬇️ https://downloads.arduino.cc/javaide/pull_requests/arduino-PR-9815-BUILD-925-linux32.tar.xz
⬇️ https://downloads.arduino.cc/javaide/pull_requests/arduino-PR-9815-BUILD-925-linux64.tar.xz
⬇️ https://downloads.arduino.cc/javaide/pull_requests/arduino-PR-9815-BUILD-925-windows.zip
⬇️ https://downloads.arduino.cc/javaide/pull_requests/arduino-PR-9815-BUILD-925-macosx.zip
⬇️ https://downloads.arduino.cc/javaide/pull_requests/arduino-PR-9815-BUILD-925-linuxarm.tar.xz

ℹ️ The linuxarm build is still experimental and may not be always available.

[ricardojlrufino]

Hi, I came to look at this LAF yesterday, what a coincidence.
would that be to pursue a true dark theme?

[ricardojlrufino]

Default light theme is not to good ( in linux )
My idea is set LAF using theme properties ... see PR #10203
I'm improving theme installation (PR #10202 ), next step try to enable a true Dark Theme

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