Function normalize_template 

pub fn normalize_template(msg: &str) -> String

Normalise a message into a template by replacing variable runs with placeholders.

Priority (highest first):

1. JSON object/array — replace the whole value with <json>
2. RFC 3164 timestamp prefix — replace leading Mon DD HH:MM:SS with <ts>
3. UUID (8-4-4-4-12 hex) → <uuid>
4. IPv4 / IPv4:port → <ip> / <ip>:<n>
5. Long hex run (≥ 8 chars) → <hex>
6. Quoted string (single or double, ≤ 200 chars) → <str>
7. Linux absolute path (/…/…) → <path>
8. Numeric run → <n>
9. Non-ASCII codepoints pass through intact.