[BugFix] Keep non-null rows for negated empty-literal MATCH in inverted-index seek

seek_inverted_index cleared the row bitmap whenever the match literal was empty
(read_inverted_index returned nullopt), regardless of negation. That dropped
every row for NOT (col MATCH ''), even though MATCH '' matches nothing and its
negation is TRUE for all non-null rows. This surfaced once the OR-MATCH fallback
started reusing seek_inverted_index.

Substitute an empty posting set for the nullopt case and reuse the shared
with_not / intersect path, so col MATCH '' keeps no rows while NOT (col MATCH '')
keeps every non-null row (only NULLs stay out). Fixes the same latent bug on the
AND filtering path. Add SQL regression for both the AND and OR-MATCH fallback
paths.

Signed-off-by: eason <1569163626@qq.com>
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Author: Beauuu-0826

be/src/storage_primitive/column_expr_predicate.cpp

@@ -392,8 +392,7 @@ Status ColumnExprPredicate::seek_inverted_index(const std::string& column_name,
 
     // nullopt means an empty match string, which matches no rows. Fall through
     // with an empty posting set so the shared logic below produces the right
-    // result: col MATCH '' keeps nothing (&= empty), while NOT (col MATCH '')
-    // keeps every non-null row (-= empty, then -= nulls).
+    // result
     if (!roaring_opt.has_value()) {
         roaring_opt.emplace();
     }