Add cross-platform keychain support using the keyring crate for secure
credential storage with biometric authentication (TouchID on macOS,
Windows Hello on Windows, Secret Service on Linux).
- Add keychain module with enable/disable biometric unlock
- Add Tauri commands for keychain operations
- Add Keychain error variant for proper error handling
- Add Java SDK foundation
- Update milestone docs to reflect 95% completion
- Update bech32 encoding to use Hrp struct and segwit::encode
- Update bip39 to use from_entropy() instead of generate_in()
- Update Mnemonic::parse() instead of parse_in(Language)
- Fix HMAC ambiguity with explicit type annotation
- Add Debug and Clone derives to EncryptedWallet
- Use show_menu_on_left_click() (deprecation fix)
- Add placeholder icons for development builds
