Fix two bugs in prototype parser

1. Inner visit at span (0,1) yielded no sub-spans because
   visit(1, 0, 1, 1) iterates span from 1 to r-x=0, which is
   empty. This prevented unary rules like [S] ||| [X,1] from
   completing at the leftmost span, so S(0,1) was never created.
   Drop the x=1 parameter (default x=0); scan already handles
   bounds checking.

2. Self-filling step searched remaining_items for unary NT rules,
   but those rules could be absent if consumed (advanced) during
   the parse loop. Look up grammar.start_nt directly instead,
   which covers all cases.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

0 files changed, 0 insertions, 0 deletions