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/decode-named-character-reference/index.dom.js

@@ -0,0 +1,36 @@
+/// <reference lib="dom" />
+
+/* global document */
+
+const element = document.createElement('i')
+
+/**
+ * @param {string} value
+ * @returns {string | false}
+ */
+export function decodeNamedCharacterReference(value) {
+  const characterReference = '&' + value + ';'
+  element.innerHTML = characterReference
+  const character = element.textContent
+
+  // Some named character references do not require the closing semicolon
+  // (`&not`, for instance), which leads to situations where parsing the assumed
+  // named reference of `&notit;` will result in the string `¬it;`.
+  // When we encounter a trailing semicolon after parsing, and the character
+  // reference to decode was not a semicolon (`&semi;`), we can assume that the
+  // matching was not complete.
+  if (
+    // @ts-expect-error: TypeScript is wrong that `textContent` on elements can
+    // yield `null`.
+    character.charCodeAt(character.length - 1) === 59 /* `;` */ &&
+    value !== 'semi'
+  ) {
+    return false
+  }
+
+  // If the decoded string is equal to the input, the character reference was
+  // not valid.
+  // @ts-expect-error: TypeScript is wrong that `textContent` on elements can
+  // yield `null`.
+  return character === characterReference ? false : character
+}