chore(main): release 0.4.2

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🤖 I have created a release beep boop

0.4.2 (2026-08-21)

Bug Fixes

• kerykeion: accept only the PSK shapes the protocol defines (#436) (c04d9a2)
• kerykeion: bound the outbound pending queue (#438) (35a5d74)
• kerykeion: bound the wire fields that were trusted to bound themselves (#435) (e7b4f45)
• kerykeion: bound what a peer can accumulate during the handshake (#437) (04c22d7)
• kryphos: derive the vault key from the parameters the vault recorded (#434) (203d75f), closes #231
• kryphos: reject a bad vault salt instead of panicking on it (#432) (486c78f)
• kryphos: report what actually failed, not the nearest familiar error (#439) (de44d50)
• semaino: make the signal path lossless end to end (#429) (f6249d5), closes #232
• syntonia: neutralize spreadsheet formulas in exported channel names (#433) (41a41d6)

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🤖 Created releases:

• v0.4.2

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