Add SelfFreezoneClient wrapper for Self components

- Created SelfFreezoneClient in Self components
- Wraps SDK FreezoneScriptClient for Self-specific operations
- Implements send_verification_email method
- Uses Rhai script template for email verification
- Includes template variable substitution
- Added serde-wasm-bindgen dependency

Usage:
  let client = SelfFreezoneClient::builder()
      .supervisor_url("http://localhost:8080")
      .secret("my-secret")
      .build()?;

  client.send_verification_email(
      "user@example.com",
      "123456",
      "https://verify.com/abc"
  ).await?;

docs/README.md

@@ -0,0 +1,37 @@
+# Self Documentation
+
+This directory contains comprehensive documentation for the Self digital identity tool.
+
+## Documentation Structure
+
+- [`architecture.md`](architecture.md) - System architecture and design principles
+- [`authentication-flows.md`](authentication-flows.md) - Detailed authentication and registration flows
+- [`server-api.md`](server-api.md) - Server API documentation and endpoints
+- [`cryptography.md`](cryptography.md) - Cryptographic implementation details
+- [`vault-system.md`](vault-system.md) - Vault functionality and key management
+- [`openid-compliance.md`](openid-compliance.md) - OpenID Connect compliance documentation
+- [`security-model.md`](security-model.md) - Security considerations and threat model
+- [`deployment.md`](deployment.md) - Production deployment guidelines
+- [`development.md`](development.md) - Development setup and contribution guide
+
+## Quick Reference
+
+### Key Concepts
+- **Self-Sovereign Identity**: Users control their own identity without relying on centralized authorities
+- **Client-Side Encryption**: All private keys are encrypted locally before storage
+- **Decentralized Authentication**: Public key-based authentication without password dependencies
+- **Vault System**: Secure storage for multiple encrypted keys with password-based access
+
+### Core Components
+- **Registration Component**: Email verification and key pair generation
+- **Login Component**: Cryptographic challenge-response authentication
+- **Identity Component**: Identity management and key access
+- **Vault Manager**: Multi-key storage and management
+- **Server**: Identity verification and OAuth-compatible endpoints
+
+### Security Features
+- AES-256-GCM encryption for private keys
+- PBKDF2-based key derivation (10,000 iterations)
+- Secp256k1 cryptographic signatures
+- JWT-based session management
+- Local storage with encrypted data only