Filtering and Pattern Matching Fixes

Negative Filter Logic: When you filter for things like "is not" or "does not contain," AnkerDB now correctly includes records with blank or missing values. You no longer have to add separate "exists false" filter to include empty values.

"Exists" Filter Behavior: The "Exists" filter behavior remains unchanged

Pattern Matching Fix: Previously, case-insensitive pattern filters in tables and validations did not consistently ignore case. These filters now correctly ignore case sensitivity in both tables and validation rules.