🔴 **This is why signing out and back in broke everything.** Sign-in only
ever consulted the in-memory `identity` field, and sign-out clears it —
so it minted a fresh `DeviceIdentity` and OVERWROTE the vault's, making
this phone a brand new device on every single sign-in.
Everything the owner hit follows from that one line:
- contacts saw a safety-number change and had to accept new keys;
- the account accumulated a registered device per sign-in, and fan-out
is per device, so half of everything sent to this account went to a
mailbox nobody reads — which is why the failures looked random and
different each time;
- the relay's public key log had not caught up with a key registered
seconds earlier, so even after accepting, the next send failed on
"the keys offered by this contact are not in the public log".
⚠️ It was harmless until it wasn't. Sign-out used to destroy the vault,
so there was never a stored identity to find and minting one was
correct. Keeping the device across a plain sign-out — which is what
makes signing out cheap — is what turned this into the bug it always
looked like. The two changes had to land together and only one did.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
