Add frontmatter, markdown, path, xml, rss, and web packages

Sync local packages into the registry repo and update index.json
and README.md to include all 9 packages.

packages/xml/test_unit.lux

@@ -0,0 +1,118 @@
+import lib
+
+// --- escape edge cases ---
+
+fn test_escape_all_chars(): Unit with {Test} = {
+    Test.assertEqualMsg("&", lib.escape("&"), "escape ampersand")
+    Test.assertEqualMsg("&lt;", lib.escape("<"), "escape less-than")
+    Test.assertEqualMsg("&gt;", lib.escape(">"), "escape greater-than")
+    Test.assertEqualMsg("&quot;", lib.escape("\""), "escape double quote")
+    Test.assertEqualMsg("&apos;", lib.escape("'"), "escape single quote")
+}
+
+fn test_escape_empty(): Unit with {Test} =
+    Test.assertEqualMsg("", lib.escape(""), "escape empty string")
+
+fn test_escape_no_special(): Unit with {Test} =
+    Test.assertEqualMsg("hello world 123", lib.escape("hello world 123"), "escape plain text unchanged")
+
+fn test_escape_all_special(): Unit with {Test} =
+    Test.assertEqualMsg("&lt;&amp;&gt;&quot;&apos;", lib.escape("<&>\"'"), "escape all special chars together")
+
+fn test_escape_mixed(): Unit with {Test} =
+    Test.assertEqualMsg("a &amp; b &lt; c", lib.escape("a & b < c"), "escape mixed content")
+
+// --- node constructors ---
+
+fn test_text_node_simple(): Unit with {Test} =
+    Test.assertEqualMsg("hello", lib.render(lib.text("hello")), "text node renders content")
+
+fn test_text_node_escapes(): Unit with {Test} =
+    Test.assertEqualMsg("&lt;script&gt;", lib.render(lib.text("<script>")), "text node escapes HTML")
+
+fn test_text_node_empty(): Unit with {Test} =
+    Test.assertEqualMsg("", lib.render(lib.text("")), "empty text node")
+
+fn test_cdata_preserves_special(): Unit with {Test} =
+    Test.assertEqualMsg("<![CDATA[<b>bold & stuff</b>]]>", lib.render(lib.cdata("<b>bold & stuff</b>")), "cdata preserves special chars")
+
+fn test_raw_no_escape(): Unit with {Test} =
+    Test.assertEqualMsg("<br/>", lib.render(lib.raw("<br/>")), "raw passes through unchanged")
+
+fn test_raw_empty(): Unit with {Test} =
+    Test.assertEqualMsg("", lib.render(lib.raw("")), "empty raw node")
+
+// --- element rendering ---
+
+fn test_self_closing_no_attrs(): Unit with {Test} =
+    Test.assertEqualMsg("<br/>", lib.render(lib.selfClosing("br", [])), "self-closing no attrs")
+
+fn test_self_closing_with_attr(): Unit with {Test} =
+    Test.assertEqualMsg("<img src=\"photo.jpg\"/>", lib.render(lib.selfClosing("img", [lib.attr("src", "photo.jpg")])), "self-closing with attr")
+
+fn test_self_closing_multiple_attrs(): Unit with {Test} = {
+    let node = lib.selfClosing("input", [lib.attr("type", "text"), lib.attr("name", "q"), lib.attr("value", "")])
+    Test.assertEqualMsg("<input type=\"text\" name=\"q\" value=\"\"/>", lib.render(node), "self-closing with multiple attrs")
+}
+
+fn test_el_empty_children(): Unit with {Test} =
+    Test.assertEqualMsg("<div/>", lib.render(lib.el("div", [])), "el with no children self-closes")
+
+fn test_el_with_children(): Unit with {Test} = {
+    let node = lib.el("ul", [lib.textEl("li", "a"), lib.textEl("li", "b")])
+    Test.assertEqualMsg("<ul><li>a</li><li>b</li></ul>", lib.render(node), "el with children")
+}
+
+fn test_text_el(): Unit with {Test} =
+    Test.assertEqualMsg("<title>Hello</title>", lib.render(lib.textEl("title", "Hello")), "textEl renders correctly")
+
+fn test_text_el_escapes(): Unit with {Test} =
+    Test.assertEqualMsg("<p>a &amp; b</p>", lib.render(lib.textEl("p", "a & b")), "textEl escapes content")
+
+fn test_text_el_attr(): Unit with {Test} = {
+    let node = lib.textElAttr("a", [lib.attr("href", "/page")], "click")
+    Test.assertEqualMsg("<a href=\"/page\">click</a>", lib.render(node), "textElAttr renders correctly")
+}
+
+// --- attribute edge cases ---
+
+fn test_attr_value_escaping(): Unit with {Test} = {
+    let node = lib.selfClosing("div", [lib.attr("data", "a&b<c\"d'e")])
+    Test.assertEqualMsg("<div data=\"a&amp;b&lt;c&quot;d&apos;e\"/>", lib.render(node), "attr value escapes all special chars")
+}
+
+fn test_attr_empty_value(): Unit with {Test} = {
+    let node = lib.selfClosing("input", [lib.attr("disabled", "")])
+    Test.assertEqualMsg("<input disabled=\"\"/>", lib.render(node), "attr with empty value")
+}
+
+// --- nesting depth ---
+
+fn test_deeply_nested(): Unit with {Test} = {
+    let deep = lib.el("a", [lib.el("b", [lib.el("c", [lib.el("d", [lib.text("deep")])])])])
+    Test.assertEqualMsg("<a><b><c><d>deep</d></c></b></a>", lib.render(deep), "4 levels deep")
+}
+
+// --- document ---
+
+fn test_document_declaration(): Unit with {Test} = {
+    let doc = lib.document(lib.textEl("root", ""))
+    Test.assert(String.startsWith(doc, "<?xml version=\"1.0\""), "document starts with XML declaration")
+}
+
+fn test_document_with_custom_decl(): Unit with {Test} = {
+    let doc = lib.documentWithDecl("<?xml version=\"1.1\"?>", lib.textEl("root", ""))
+    Test.assert(String.startsWith(doc, "<?xml version=\"1.1\"?>"), "custom declaration")
+}
+
+// --- mixed children ---
+
+fn test_mixed_children_types(): Unit with {Test} = {
+    let node = lib.el("div", [
+        lib.text("Hello "),
+        lib.raw("<strong>world</strong>"),
+        lib.text(" & "),
+        lib.cdata("raw data")
+    ])
+    Test.assertEqualMsg("<div>Hello <strong>world</strong> &amp; <![CDATA[raw data]]></div>", lib.render(node), "mixed children types")
+}