When the dashboard user browses another agent's mailbox (e.g. the CEO's
inbox), opening a message no longer triggers POST /messages/:id/read.
The previous behavior silently consumed the agent's unread state, so the
agent's heartbeat never surfaced the message and fn_read_messages (which
defaults to unread_only=true) returned nothing. Auto-mark-read now only
fires on the dashboard user's own inbox tab. Adds regression tests in
MailboxView.test.tsx and MailboxModal.test.tsx.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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