Function detect_pattern 

pub fn detect_pattern(value: &str) -> Option<PatternType>

Detect pattern type from a string value.

Checks patterns in order of specificity:

1. UUID (most specific format)
2. ObjectId (24 hex chars)
3. JWT (three base64 segments)
4. Email
5. ISO Date
6. URL
7. IPv4
8. IPv6
9. Phone
10. Credit Card
11. Hex String (generic fallback for hex)

Returns None if no pattern matches.

Performance

Average: ~200ns for non-matching strings Worst case: ~1us when checking all patterns