Fix display of TABs in hscrolled windows with line numbers

Fix display of TABs in hscrolled windows with line numbers

* src/dispextern.h (struct it): New members tab_offset and
line_number_produced_p.
* src/xdisp.c (display_line): Don't set row->x to a negative value
if line numbers are being displayed.  (Bug#30582)
Reset the line_number_produced_p flag before laying out the glyph
row.
(x_produce_glyphs): Use the line_number_produced_p flag to decide
whether to offset the X coordinate due to line-number display.
Use the tab_offset member to restore the original TAB width for
alignment purposes.
(move_it_in_display_line_to): Don't produce line numbers when moving
in hscrolled window to the left of first_visible_x.
(maybe_produce_line_number): Set the line_number_produced_p flag.
(Bug#30584)
* src/term.c (produce_glyphs): Correct TAB width only when
line_number_produced_p flag is set.