feat: add size and box alpha for held buttons

[Keith94]

Added:

• button_held_size - sets the scale of a button when held/pressed, independent of button_hover_size. Previously, holding a button always reset the scale back to 100%.

• button_held_box_alpha - sets the transparency of the hover background box when a button is held down. Defaults to 0xCC (~80% transparent), brighter than the standard hover box at 0xE6 (~90% transparent).

[Samillion]

Thank you very much.

My only note is the way alpha will be set by users, at least 90% of users will not know what that value means or what it should be.

Would my opacity convert function from pause indicator help you here? so that it would be a 0-100 value instead.

ModernZ/extras/pause-indicator-lite/pause_indicator_lite.lua

Lines 95 to 99 in 79fbbfb

	-- convert percentage opacity (0-100) to ASS alpha values
	local function convert_opacity(value)
	value = math.max(0, math.min(100, value))
	return string.format("%02X", (255 - (value * 2.55)))
	end

[Keith94]

That's a great idea. I've added it to the PR now.

[Samillion]

Awesome, thank you very much. Let me know when it's merge ready, please.

Side note:
This PR and the gap chapter PR made me realize there is a whole bunch of dead code, wrong code and redundant code still left.

Specifically in osc_styles, layouts and osc_init.

[Keith94]

It's good to go.

Still it's an accomplishment how much code you got cleaned up. I'll try to help anyways.