feat: Working on node builder

Sources/CliDoc/NodeBuilder.swift

@@ -0,0 +1,31 @@
+@resultBuilder
+public enum NodeBuilder {
+
+  public static func buildPartialBlock<N: NodeRepresentable>(first: N) -> N {
+    first
+  }
+
+  public static func buildPartialBlock<N0: NodeRepresentable, N1: NodeRepresentable>(
+    accumulated: N0,
+    next: N1
+  ) -> _ManyNode {
+    .init([accumulated, next], separator: .empty())
+  }
+
+  public static func buildArray<N: NodeRepresentable>(_ components: [N]) -> _ManyNode {
+    .init(components, separator: .empty())
+  }
+
+  public static func buildEither<N0: NodeRepresentable, N1: NodeRepresentable>(
+    first component: N0
+  ) -> _ConditionalNode<N0, N1> {
+    .first(component)
+  }
+
+  public static func buildEither<N0: NodeRepresentable, N1: NodeRepresentable>(
+    second component: N1
+  ) -> _ConditionalNode<N0, N1> {
+    .second(component)
+  }
+
+}