The email-activity panel surfaced every captured message, including cold/
unknown-sender email with no investor association. Gate query_email_activity
on EXISTS(email_investor_links) so the panel shows only email tied to a known
investor/contact. Capture is unchanged — unmatched email is still stored
(metadata-only) and will appear automatically if its sender is later added as
an investor; this is a read-side filter only.
Graveyard investors are unaffected (their email has a link), so they remain
visible/searchable as an audit surface, hidden only from the filter picker.
Keysat