Remove cloning in generic_damerau_levenshtein

[Unparalleled-Calvin]

Hi there! This PR modifies the generic_damerau_levenshtein implementation to:

• Use borrowed elements (&Elem) as HashMap keys instead of owned values
• Eliminate unnecessary .clone() calls
• Allow broader use cases for types where cloning is expensive or impossible

Benefits:

• Faster execution
• Supports non-Clone element types
• Reduces memory allocations