Fallback to hack when `get_term_size` via syscall is not implemented

[RaphGL]

This was implemented before but got yeeted out before (don't remember why). I've looked at it but for some reason it was not working unless a debugger is attached.

How this should work (if syscall fails):

1. Use ANSI escape code to move cursor to a high position like x: 99,999 y:99,999
2. Ask the terminal what position the cursor is in
3. Parse and return the cursor position

[RaphGL]

I've looked and this is due to the fact that canonical mode is buffers everything and only flushes on pressing enter. Apparently this behavior cannot be overriden. So this could only be done for Raw mode. Alternatively we could hack our way through by just changing the terminal mode, getting the cursor value then restore the terminal and continue. But I'm worried if this is not very slow.

---

I've managed to implement this but decided to remove it cause I was getting an error with write_string when slicing.

The implementation of the cursor retrieval and parsing from the terminal can be taken from

TermCL/termcl.odin

Lines 420 to 450 in 26d9545

	// Get the current cursor position.
	get_cursor_position :: proc(win: $T/^Window) -> (pos: Cursor_Position, success: bool) {
	if win.width == nil && win.height == nil {
	fmt.print("\x1b[6n")
	input, has_input := read(win)
	if !has_input || len(input) < 6 {
	return
	}
	if input[0] != '\x1b' && input[1] != '[' do return
	if input[len(input) - 1] != 'R' do return
	input_str := cast(string)input[2:len(input) - 1]
	consumed: int
	y, _ := strconv.parse_uint(input_str, n = &consumed)
	input_str = input_str[consumed:]
	if input_str[0] != ';' do return
	input_str = input_str[1:]
	x, _ := strconv.parse_uint(input_str, n = &consumed)
	input_str = input_str[consumed:]
	if len(input_str) != 0 do return
	return Cursor_Position{x = x - 1, y = y - 1}, true
	} else {
	return win.cursor, true
	}
	}

and the get_term_size is along the lines of what is here:

TermCL/termcl.odin

Lines 390 to 399 in 26d9545

	curr_pos, _ := get_cursor_position(screen)
	MAX_CURSOR_POSITION :: ansi.CSI + "9999;9999H"
	fmt.print(MAX_CURSOR_POSITION)
	pos, _ := get_cursor_position(screen)
	// restore cursor position
	fmt.printf(ansi.CSI + "%d;%dH", curr_pos.y, curr_pos.x)
	return Screen_Size{w = pos.x, h = pos.y}