fix(presentation): extract 12 handler violations to use cases

- TokenService port + JwtTokenService adapter; login/refresh return LoginResult
- delete get_token (dup of login); create_tokens helper removed
- type UpdateChannelRequest schedule_config/recycle_policy (no serde_json::Value)
- update_settings returns updated Vec; handler calls one use case
- config use case in application::config; handler maps DTO only
- SyncStatusEntry moved to api-types w/ From<LibrarySyncLogEntry>
- trigger_sync: Conflict error, drop sync_trigger.send from handler
- UpsertProviderCommand.config accepts Value; serialization in use case
- get_current_broadcast returns BroadcastWithChannel; one call
- get_stream_url resolves broadcast internally; handler single call

crates/adapters/auth/src/lib.rs

@@ -6,4 +6,4 @@ pub mod jwt;
 pub use password::PasswordAuthService;
 
 #[cfg(feature = "jwt")]
-pub use jwt::{JwtClaims, JwtConfig, JwtError, JwtValidator};
+pub use jwt::{JwtClaims, JwtConfig, JwtError, JwtTokenService, JwtValidator};