fix(e2ee): skip signcrypt timestamp check for archived messages#429
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The XEP-0373 signcrypt envelope carries a <time/> element checked against a ±7-day skew window to prevent replay attacks. This check compared against Date.now() even for MAM-replayed and retried messages, causing permanent decryption failure for any message older than 7 days. On a second device that restores the key after the messages were received, retryPendingDecrypts would re-attempt decryption but always fail the timestamp check — the messages were authentically old. Add fromArchive to InboundDecryptContext, set it for archive-sourced stanzas and retry paths, and skip the skew check when set. The check remains active for live messages where replay defence matters.
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Summary
<time/>skew check compared againstDate.now()even for MAM-replayed and retried messages, causing permanent decryption failure for any message older than 7 days.retryPendingDecryptswould always fail because the messages are authentically old.fromArchivetoInboundDecryptContext, propagated fromstanzaDecryptwhensource === 'archive'. The OpenPGP plugin skips the ±7-day skew check when this flag is set. Live messages still enforce the anti-replay window.