Add a 1px padding on each edge when creating the bitmap, this guarantees enough space for fractional/anti-aliased edges across all DPIs and devices.

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What is the current behavior?

Right now, font icons used in Image or ActionItem etc (font://...) mitght get clipped on the top and right on certain devices/dpis, 1px is missing on top and right.

This is because NativeScript currently uses:

paint.getTextBounds(source, 0, source.length, textBounds);
const bitmap = Bitmap.createBitmap(textBounds.width(), textBounds.height(), ...);
canvas.drawText(source, -textBounds.left, -textBounds.top, paint);

getTextBounds returns an integer rectangle, rounded down.
The actual glyph rasterization may extend slightly beyond this box due to fractional scaling and anti-aliasing.

What is the new behavior?

1px padding is added on each edge when creating the bitmap:

const padding = 1;
const bitmap = Bitmap.createBitmap(
    textBounds.width() + padding * 2,
    textBounds.height() + padding * 2,
    Bitmap.Config.ARGB_8888
);
canvas.drawText(
    source,
    -textBounds.left + padding,
    -textBounds.top + padding,
    paint
);

This guarantees enough space for fractional/anti-aliased edges across all DPIs and devices.

Fixes/Implements/Closes #10857 .