Android: Fix DisplayServer.get_display_safe_area() issues

[syntaxerror247]

DisplayServer.get_display_safe_area() was previously unreliable:

• It did not account for dock/taskbar on tablets.
• In landscape mode, it failed to account for the cutout area.
• In reverse portrait, it would double-subtract the cutout, resulting in an incorrect safe area.
• If edge-to-edge mode was disabled, it gave more incorrect area, etc.

This PR rewrites the safe area logic to address all of these cases. It now reliably returns the correct safe area in my testing with different physical and virtual devices.

Fixes #105462

Test Project: safe_area_test.zip

[Alex2782]

Test, Video - LG Nexus 5X - Android 8, Edge to Edge + Immersive Mode

test_nexus5x.mp4

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on Samsung Tab S7 - Android 13

master branch, 51px of the status bar was not taken into account (only edge ​​to edge, without Immersive Mode)

[P: (0, 51), S: (2560, 1498)]
[P: (0, 51), S: (1600, 2458)]

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this PR. (1498 - 1447 = 51)

[P: (0, 51), S: (2560, 1447)]
[P: (0, 51), S: (1600, 2407)]

[Alex2782]

Fixes also #62783 ? (v3.4.4 after cherrypick maybe)

[Repiteo]

Thanks!