NapiServerHandler was bypassing IdentityProvider, calling
config.auth.authenticate_publickey() directly, which meant no Identity
was stored on the session and per-identity forwarding rules could not
match. It also skipped ForwardingPolicy::check() entirely, defeating
forwarding access control for NAPI-served tunnels. Both are now
consistent with ServerHandler and SshHandler behavior.
- Add reloadAuth(), reloadForwarding(), reloadAll() methods to AlknetServer
- Add NAPI type definitions: AuthConfigNapi, ForwardingPolicyConfig, ForwardingRuleConfig
- Refactor NapiServerHandler to use ArcSwap<DynamicConfig> for atomic config swaps
- Add ConfigReloadHandle::dynamic_arc() accessor for sharing ArcSwap between NAPI and accept loop
- Add ipnetwork dependency to alknet-napi for TargetPattern CIDR parsing
- Add builder functions for AuthPolicy and ForwardingPolicy from NAPI config types
- All swaps are atomic via ArcSwap per ADR-030
Split alknet-core configuration into StaticConfig (immutable after startup)
and DynamicConfig (hot-reloadable at runtime via ArcSwap).
- Add StaticConfig struct in config/static_config.rs with all fields per ADR-030
- Add DynamicConfig struct with AuthPolicy, ForwardingPolicy, RateLimitConfig
- Add ForwardingPolicy with allow_all()/deny_all() defaults (ADR-031)
- Add ConfigReloadHandle with reload() method for runtime config updates
- Replace Arc<ServerAuthConfig> with Arc<ArcSwap<DynamicConfig>> in ServerHandler
- Add config_reload_handle() to Server for obtaining reload handles
- Add AuthPolicy with authenticate_publickey/authenticate_certificate methods
- All existing tests pass with the new config structure
- Default DynamicConfig produces identical behavior to current code
