Clipboard: Pasting UTF-8 multibyte sequences broken

[vain]

The pasting code iterates over the bytes we read from wl-paste/xclip and that breaks when you try to paste multibyte sequences:

bemenu/lib/menu.c

Lines 1199 to 1203 in 5bc8a6c

	for (size_t i = 0; i < pasted_len; i++) {
	size_t width;
	menu->cursor += bm_unicode_insert(&menu->filter, &menu->filter_size, menu->cursor, pasted_buf[i], &width);
	menu->curses_cursor += width;
	}

As an example, select this character: ö and try to paste it.

The code calls bm_unicode_insert(), which expects unicode codepoints, not raw bytes. We have to UTF-8-decode the whole string first.