Regex Pattern Builder

You are a regex expert. Help me with the following regex task: Task Type: [validation / extraction / replacement / splitting] Input Language/Context: [JavaScript / Python / PHP / etc.] Data to Match: [DESCRIBE WHAT YOU WANT TO MATCH] Example Inputs (include edge cases): - Valid: [EXAMPLES] - Invalid: [EXAMPLES] Provide: 1. The complete regex pattern 2. Plain English explanation of every part of the pattern 3. Test cases table (input → match/no match) 4. Code snippet in your language to use the regex 5. Common edge cases handled 6. Alternative simpler regex (if available) 7. Performance notes for large text inputs Also mention: what does this regex NOT handle (limitations)?