feat: 4337 sdk auth server

[JackHamer09]

Description

• Move all packages/workflows to 4337 SDK, this includes demo-app, auth server and removing any use of legacy sdk
• New Auth Server API used for smart account deployments.
• Add configurable alto bundler server with cors proxy.
• Removed bank demo

Additional context

The plan later is to completely remove all legacy SDK/contracts from the folder and rename 4337 one's (e.g. sdk-4337 -> sdk)

[github-actions]

Visit the preview URL for this PR (updated for commit bf45ce2):

https://zksync-auth-server-staging--pr228-4337-sdk-auth-server-t34a1nt4.web.app

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[Copilot]

Pull request overview

This PR implements a major migration from the legacy SDK to the 4337 SDK architecture, introducing account abstraction (ERC-4337) support and a new auth server API. The changes include moving all packages and workflows to the 4337 SDK, implementing a configurable Alto bundler with CORS proxy, and removing the legacy bank demo.

Key changes:

• Complete restructuring of SDK packages with new 4337-based implementations
• New auth server API for smart account deployments
• Introduction of Alto bundler with CORS proxy for browser compatibility
• Migration of authentication and session management to ERC-4337 standard

Reviewed changes

Copilot reviewed 200 out of 237 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
packages/sdk-platforms/web/src/webauthn.ts	Updated WebAuthn credential structure to nest public key coordinates
packages/sdk-4337/src/version.ts	Added library version constant
packages/sdk-4337/src/index.ts	New main export file for SDK modules
packages/sdk-4337/src/errors/*	Complete error handling system implementation
packages/sdk-4337/src/connector/index.ts	Wagmi connector implementation for ZKsync SSO
packages/sdk-4337/src/communicator/*	Popup-based communication system
packages/sdk-4337/src/client/session/*	Session management with monitoring and formatting
packages/sdk-4337/src/client/passkey/*	Passkey client implementation
packages/sdk-4337/src/client/actions/*	Session and deployment actions
packages/sdk-4337/src/client-auth-server/*	Auth server RPC types and wallet provider
packages/sdk-4337/src/abi/*	Contract ABIs for validators
packages/bundler/*	New Alto bundler with CORS proxy
packages/auth-server/*	Updated to use 4337 SDK with API-based deployments
packages/connector-export/*	Removed (consolidated into main SDK)

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[cpb8010]

Ok I read everything (that wasn't deleted or moved).

Main things to follow up:

1. Guardian, OIDC (WIP), demo-app signer, session support on deployment, bank-demo
2. Very small name changes to session and passkey clients is probably an upgrade
3. Bundler proxy probably needs more devops thoughts?