XLSX-Konverter: Bessere Fehlermeldung bei inkorrektem Typ in Spalte, zusätzlicher Spalte

Summary

Type and Validation errors are now collected and formatted as a table. The error raised when there is an additional column not present in the schema now describes the problem. Addresses https://gitlab.indiscale.com/caosdb/customers/dimr/management/-/issues/251

Focus

• Does this solution improve readability and error identification? (is it a 'better output'?)
• Are all errors covered?

Test Environment

Manual testing.

Check List for the Author

• All automated tests pass
• Reference related issues
• Up-to-date CHANGELOG.md (not necessary)
• Appropriate user and developer documentation (or not necessary)
• Annotations in code (Gitlab comments)

Check List for the Reviewer

• I understand the intent of this MR
• All automated tests pass
• Up-to-date CHANGELOG.md (or not necessary)
• Appropriate user and developer documentation (or not necessary)
• The test environment setup works and the intended behavior is reproducible in the test environment
• In-code documentation and comments are up-to-date.
• Check: Are there specifications? Are they satisfied?