public void tabBack() {
		if (curX == 0) {
			return;
		}
		int n = (curX - 1) % TAB_WIDTH + 1;
		moveCursorLeft(n, false);
	}
Move the cursor backward to the previous tab stop
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/terminal/vt/VtBuffer.java