Match quoted glob chars literally in [[ == ]] patterns (batch87)

[brianjfox]

Summary

The right-hand side of [[ word == pattern ]] (and !=) is a pattern in which a quoted or backslash-escaped glob metacharacter matches literally, but CondEval expanded it with expand_no_split (quote removal), so the protecting quotes were stripped before strmatch:

$ [[ abc == a\* ]]; echo $?      # was 0 (matched)  → now 1
$ [[ ab == a"*" ]]; echo $?      # was 0            → now 1
$ [[ axb == a"*"b ]]; echo $?    # was 0            → now 1

Fix: expand the ==/!= right-hand side with expand_pattern (which backslash-escapes quoted glob chars while leaving unquoted ones active) — the same expansion the case statement already uses. Active (unquoted) globs still match.

Testing

• ctest 22/22
• Scoreboard: cond 79 → 75, comsub2 37 → 35 (bonus), zero regressions
• Verified quoted/escaped vs active glob (*/?), ==/!=, and literal cases against bash 5.3

Closes #291.