Refactor routing in App component to enhance navigation and improve error handling by integrating dynamic routes and updating the NotFound route.

node_modules/micromark-util-normalize-identifier/dev/index.js

@@ -0,0 +1,38 @@
+import {values} from 'micromark-util-symbol'
+
+/**
+ * Normalize an identifier (as found in references, definitions).
+ *
+ * Collapses markdown whitespace, trim, and then lower- and uppercase.
+ *
+ * Some characters are considered “uppercase”, such as U+03F4 (`ϴ`), but if their
+ * lowercase counterpart (U+03B8 (`θ`)) is uppercased will result in a different
+ * uppercase character (U+0398 (`Θ`)).
+ * So, to get a canonical form, we perform both lower- and uppercase.
+ *
+ * Using uppercase last makes sure keys will never interact with default
+ * prototypal values (such as `constructor`): nothing in the prototype of
+ * `Object` is uppercase.
+ *
+ * @param {string} value
+ *   Identifier to normalize.
+ * @returns {string}
+ *   Normalized identifier.
+ */
+export function normalizeIdentifier(value) {
+  return (
+    value
+      // Collapse markdown whitespace.
+      .replace(/[\t\n\r ]+/g, values.space)
+      // Trim.
+      .replace(/^ | $/g, '')
+      // Some characters are considered “uppercase”, but if their lowercase
+      // counterpart is uppercased will result in a different uppercase
+      // character.
+      // Hence, to get that form, we perform both lower- and uppercase.
+      // Upper case makes sure keys will not interact with default prototypal
+      // methods: no method is uppercase.
+      .toLowerCase()
+      .toUpperCase()
+  )
+}