Complete 5-file learn documentation for the advanced encrypted P2P chat
project covering Signal Protocol (X3DH + Double Ratchet), WebAuthn/Passkeys,
and the fullstack architecture.
Ref #51
- Add headers, badges, learn module pointers, just command runner tips, and AGPLv3 licenses etc. etc.
- Add missing Justfiles in some projects
- Update pre commit hook and add TODO