Remove daemon mode references and unused config fields

The --daemon flag, BackupInterval, FullScanInterval, MinTimeBetweenRun
config fields, and DirtyPath model were placeholders for a never-shipped
daemon mode and have been removed. Daemon mode is out of scope for 1.0.

internal/cli/snapshot.go

@@ -98,7 +98,6 @@ specifying a path using --config or by setting VAULTIK_CONFIG to a path.`,
 		},
 	}
 
-	cmd.Flags().BoolVar(&opts.Daemon, "daemon", false, "Run in daemon mode with inotify monitoring")
 	cmd.Flags().BoolVar(&opts.Cron, "cron", false, "Run in cron mode (silent unless error)")
 	cmd.Flags().BoolVar(&opts.Prune, "prune", false, "Delete all previous snapshots and unreferenced blobs after backup")
 	cmd.Flags().BoolVar(&opts.SkipErrors, "skip-errors", false, "Skip file read errors (log them loudly but continue)")