StoredDocument.expiresAt is the optional expiry timestamp for a stored PDF. It is computed from options.ttlDays as the render time plus that many days (ttlDays * 86400000 ms), or left null when no TTL is given, meaning the document never expires. The value is returned in the store-mode render response and in GET /api/documents listings so callers can show or honor it. The expiresAt column is indexed and drives the POST /api/internal/cleanup job, which removes documents whose expiresAt has passed.
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StoredDocument.expiresAt
When a StoredDocument becomes eligible for automatic cleanup, or null to never expire.