TDT-2789 Clarify event visibility default is Google-only (Create Personal Website Free)

Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>

Author: How To Hyperlink In Instagram Post

CHANGELOG.md

@@ -2,6 +2,7 @@ nylas-python Changelog
 ======================
 Unreleased
 ----------
+* Clarify that event `default` visibility is Google-only
 
 v6.16.0
 ----------

nylas/models/events.py

@@ -10,7 +10,13 @@
 """ Literal representing the status of an Event. """
 
 Visibility = Literal["default", "public", "private"]
-""" Literal representation of visibility of the Event. """
+"""
+Literal representation of visibility of the Event.
+
+`default` is only valid for Google events, where it defers to the calendar's own sharing
+settings. Microsoft and EWS events only support `public` and `private`; sending `default`
+for these providers returns a 400 error.
+"""
 
 ParticipantStatus = Literal["noreply", "yes", "no", "maybe"]
 """ Literal representing the status of an Event participant. """