chore: remove database files from git tracking

- Add project_db/ and query_db/ to .gitignore
- Remove local database files from version control
- These files contain user credentials and should never be committed

Author: matheuscamposmt

.gitignore

@@ -30,3 +30,7 @@ dist-ssr
 # Local sled databases
 project_db
 query_db
+
+/src-tauri/project_db# Local databases (should never be committed)
+src-tauri/project_db/
+src-tauri/query_db/