chore: update .gitignore to exclude todo files

Enhanced `.gitignore` to filter out case-sensitive variations
of TODO markdown files. This ensures that personal or temporary
task lists don't clutter the repository, maintaining a clean
project space.

.gitignore

@@ -451,5 +451,8 @@ temp
 .tmp
 .temp
 
+# Temporary files case sensitive todo markdown
+*[Tt][Oo][Dd][Oo].md
+
 # Extension sqltools connections secrets
 .vscode*