I'm using alternation (|) to match each of the 12 target items exactly. For each item:
1. I've carefully escaped all regex special characters like brackets [], parentheses (), braces {}, plus +, asterisk *, dot ., backslash \, etc.
2. For items with backslashes like the math expressions, I've properly escaped those in the regex.
3. The reference IDs follow a specific format and I've matched them precisely.
4. For the complex nested structures like "[[{x: (2.5 * π), y: \\{escaped\\}}]]", I've meticulously escaped each special character.
5. The URLs contain many special characters that need escaping, especially the one with IPv6 address and escaped braces.

This approach ensures we match exactly and only the specified targets.