feat: initialize markr nostr bookmark client

- Add project structure with TypeScript, React, and Vite
- Implement nostr authentication using browser extension (NIP-07)
- Add NIP-51 compliant bookmark fetching and display
- Create minimal UI with login and bookmark components
- Integrate applesauce-core and applesauce-react libraries
- Add responsive styling with dark/light mode support
- Include comprehensive README with setup instructions

This is a minimal MVP for a nostr bookmark client that allows users to
view their bookmarks according to NIP-51 specification.

node_modules/eslint/lib/cli-engine/formatters/checkstyle.js

@@ -0,0 +1,60 @@
+/**
+ * @fileoverview CheckStyle XML reporter
+ * @author Ian Christian Myers
+ */
+"use strict";
+
+const xmlEscape = require("../xml-escape");
+
+//------------------------------------------------------------------------------
+// Helper Functions
+//------------------------------------------------------------------------------
+
+/**
+ * Returns the severity of warning or error
+ * @param {Object} message message object to examine
+ * @returns {string} severity level
+ * @private
+ */
+function getMessageType(message) {
+    if (message.fatal || message.severity === 2) {
+        return "error";
+    }
+    return "warning";
+
+}
+
+//------------------------------------------------------------------------------
+// Public Interface
+//------------------------------------------------------------------------------
+
+module.exports = function(results) {
+
+    let output = "";
+
+    output += "<?xml version=\"1.0\" encoding=\"utf-8\"?>";
+    output += "<checkstyle version=\"4.3\">";
+
+    results.forEach(result => {
+        const messages = result.messages;
+
+        output += `<file name="${xmlEscape(result.filePath)}">`;
+
+        messages.forEach(message => {
+            output += [
+                `<error line="${xmlEscape(message.line || 0)}"`,
+                `column="${xmlEscape(message.column || 0)}"`,
+                `severity="${xmlEscape(getMessageType(message))}"`,
+                `message="${xmlEscape(message.message)}${message.ruleId ? ` (${message.ruleId})` : ""}"`,
+                `source="${message.ruleId ? xmlEscape(`eslint.rules.${message.ruleId}`) : ""}" />`
+            ].join(" ");
+        });
+
+        output += "</file>";
+
+    });
+
+    output += "</checkstyle>";
+
+    return output;
+};