refactor: rename passkeyChallenge to webauthnChallenge

- Renamed table for consistency with webauthnCredentials
- Created migration script 1.8.1.ts for table rename
- Updated schema definitions in SQLite and PostgreSQL
- Maintains WebAuthn standard naming convention

server/routers/auth/index.ts

@@ -12,3 +12,4 @@ export * from "./resetPassword";
 export * from "./checkResourceSession";
 export * from "./setServerAdmin";
 export * from "./initialSetupComplete";
+export * from "./passkey";