### 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.
if (selection.enabled && !p_select) {
		set_caret_column(selection.end);
		deselect();
		return;
	}
	shift_selection_check_pre(p_select);
	if (p_move_by_word) {
		int cc = caret_column;
		PackedInt32Array words = TS->shaped_text_get_word_breaks(text_rid);
		for (int i = 1; i < words.size(); i = i + 2) {
			if (words[i] > cc) {
				cc = words[i];
				break;
			}
		}
		set_caret_column(cc);
	} else {
		if (caret_mid_grapheme_enabled) {
			set_caret_column(get_caret_column() + 1);
		} else {
			set_caret_column(TS->shaped_text_next_grapheme_pos(text_rid, get_caret_column()));
		}
	}
	shift_selection_check_post(p_select);
	_reset_caret_blink_timer();
}
void LineEdit::_move_caret_start(bool p_select) {