feat: Initial commit

Sources/CliDoc/Nodes/Group.swift

@@ -0,0 +1,28 @@
+/// A group container holding one or more nodes.
+public struct Group: Node {
+  var nodes: [any Node]
+  var separator: String
+
+  init(_ nodes: [any Node], separator: String = "\n") {
+    self.nodes = nodes
+    self.separator = separator
+  }
+
+  public init(
+    separator: String = " ",
+    @NodeBuilder build: () -> any Node
+  ) {
+    let node = build()
+    if var group = node as? Self {
+      group.separator = separator
+      self = group
+    } else {
+      self.init([node], separator: separator)
+    }
+  }
+
+  public var body: some Node {
+    nodes.map { $0.render() }.joined(separator: separator)
+  }
+
+}