684ee222ad
Wire up the config parsing infrastructure into the server: - NatsServer: add ReloadConfig() with digest-based change detection, diff/validate, CLI override preservation, and side-effect triggers - Program.cs: two-pass CLI parsing — load config file first, then apply CLI args on top with InCmdLine tracking for reload precedence - SIGHUP handler upgraded from stub warning to actual reload - Remove config file "not yet supported" warning from StartAsync - Add integration tests for config loading, CLI overrides, and reload validation