[#293] Document passkey signer flow

modules/passkey/README.md

@@ -1,3 +1,28 @@
 # Passkey
 
 This package contains a passkey signature verifier, that can be used as an owner for a Safe, compatible with versions 1.3.0+.
+
+## Execution flow
+
+```mermaid
+sequenceDiagram
+actor U as User
+participant CS as CredentialStore
+participant SPF as SafeProxyFactory
+participant WASF as WebAuthnSignerFactory
+participant SSL as SafeSignerLaunchpad
+participant SS as SafeSingleton
+participant SP as SafeProxy
+participant WAV as WebAuthnVerifier
+participant PV as P256Verifier
+actor T as Target
+
+U->>+CS: Create Credential (User calls `create(...)`)
+CS->>U: Decode public key from the return value
+U->>+WASF: Get signer address (signer might not be deployed yet) 
+WASF->>U: Signer address
+U->>+SPF: Submit Payload that calculates SafeProxy address with SafeSignerLaunchpad as singleton and corresponding initializer data
+U->>+Bundler: Submit Payload that contains init code to deploy SafeProxy and callData containing initializer data and UserOp
+Bundler->>SPF: Deploy SafeProxy
+
+```