ParseSubmitIndexExpr accepts only name[1-N] and name[1] (leading zeros
allowed) and otherwise reports the lowest-numbered broken rule with its
specific message: interactive arrays (2.1), invalid name or malformed
expression (2.2), lists/steps (2.3), %N (2.4), start 0 (2.5), reversed
(2.6), start above 1 (2.7), above the limit (2.8). Oversized numbers
saturate for the bound checks while reversal compares the digit
strings, so the rule order holds for any input. Not yet wired into
CreateJob (task 6.2).
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>