feat: Enhance communication and documentation for standup context and work item clarity

ai/context/process/communication.md

@@ -21,6 +21,9 @@ When the format fits, prefer:
 - Always clarify authenticated vs non-authenticated when behavior depends on it.
 - Always separate external issues from regressions.
 - Always state reproducibility and scope.
+- For standups, report the previous workday context, not blindly the prior calendar day.
+- On Mondays, use Friday's work context unless a later prior day has Mattermost activity.
+- If the previous calendar day has no project activity because of weekend, holiday, or OOO, use the latest prior day with Mattermost activity.
 - Avoid vague phrasing such as:
   - "same behavior"
   - "looks fixed"