Database check and migration scripts

[ErMichele]

Created two SQL scripts to assist with database debugging:

1. UserCheck.sql: Shows the first 5 users in the database along with all their associated tasks.
2. DuplicatedMigrationFix.sql: Removes duplicated categories caused by previous case‑insensitive behavior and converts all category names to uppercase to match the new application configuration (as seen in Fixed duplicated categories #4)