Update constants.py

Added regex comment

Author: tristanlabelle

app/backend/src/couchers/constants.py

@@ -15,6 +15,8 @@
 # Must match the frontend values in app/web/utils/validation.ts
 VALID_NAME_MIN_LENGTH = 2
 VALID_NAME_MAX_LENGTH = 100
+
+# Letters, diacritics, internal spaces, quotes, dashes, commas, dots, and's for two names. See tests!
 VALID_NAME_REGEX = r"""^(?!\p{Zs})[\p{L}\p{M}\p{Zs}\p{Pi}\p{Pf}\p{Pd},.'"·・&/|]+(?<!\p{Zs})$"""
 
 BANNED_USERNAME_PHRASES = [