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/micromark-core-commonmark/lib/character-escape.js

@@ -0,0 +1,64 @@
+/**
+ * @import {
+ *   Construct,
+ *   State,
+ *   TokenizeContext,
+ *   Tokenizer
+ * } from 'micromark-util-types'
+ */
+
+import { asciiPunctuation } from 'micromark-util-character';
+/** @type {Construct} */
+export const characterEscape = {
+  name: 'characterEscape',
+  tokenize: tokenizeCharacterEscape
+};
+
+/**
+ * @this {TokenizeContext}
+ *   Context.
+ * @type {Tokenizer}
+ */
+function tokenizeCharacterEscape(effects, ok, nok) {
+  return start;
+
+  /**
+   * Start of character escape.
+   *
+   * ```markdown
+   * > | a\*b
+   *      ^
+   * ```
+   *
+   * @type {State}
+   */
+  function start(code) {
+    effects.enter("characterEscape");
+    effects.enter("escapeMarker");
+    effects.consume(code);
+    effects.exit("escapeMarker");
+    return inside;
+  }
+
+  /**
+   * After `\`, at punctuation.
+   *
+   * ```markdown
+   * > | a\*b
+   *       ^
+   * ```
+   *
+   * @type {State}
+   */
+  function inside(code) {
+    // ASCII punctuation.
+    if (asciiPunctuation(code)) {
+      effects.enter("characterEscapeValue");
+      effects.consume(code);
+      effects.exit("characterEscapeValue");
+      effects.exit("characterEscape");
+      return ok;
+    }
+    return nok(code);
+  }
+}