### Godot version

v4.1.beta.custom_build [d3651ea45]

### System information

Windows 11

### Issue description

![1](https://github.com/godotengine/godot/assets/28705694/15c14c93-7ad7-425a-8fb0-bef841b75527)

It's not possible to start text selection on a SpinBox when it's unfocused.

Note: After a bit of digging in the code, I found that clicking on a SpintBox doesn't trigger `SpinBox::gui_input` no matter if it's focused or not. However, releasing mouse left button does trigger the function.

### Steps to reproduce

See the gif.

### Minimal reproduction project

It's simple to reproduce.
Ref<StyleBox> style = theme_cache.normal;
	bool rtl = is_layout_rtl();
	int x_ofs = 0;
	float text_width = TS->shaped_text_get_size(text_rid).x;
	switch (alignment) {
		case HORIZONTAL_ALIGNMENT_FILL:
		case HORIZONTAL_ALIGNMENT_LEFT: {
			if (rtl) {
				x_ofs = MAX(style->get_margin(SIDE_LEFT), int(get_size().width - style->get_margin(SIDE_RIGHT) - (text_width)));
			} else {
				x_ofs = style->get_offset().x;
			}
		} break;
		case HORIZONTAL_ALIGNMENT_CENTER: {
			if (!Math::is_zero_approx(scroll_offset)) {
				x_ofs = style->get_offset().x;
			} else {
				x_ofs = MAX(style->get_margin(SIDE_LEFT), int(get_size().width - (text_width)) / 2);
			}
		} break;
		case HORIZONTAL_ALIGNMENT_RIGHT: {
			if (rtl) {
				x_ofs = style->get_offset().x;
			} else {
				x_ofs = MAX(style->get_margin(SIDE_LEFT), int(get_size().width - style->get_margin(SIDE_RIGHT) - (text_width)));
			}
		} break;
	}