Add FolderSelector component and integrate with CreateFileModal

app/src/utils/fileTreeUtils.ts

@@ -0,0 +1,44 @@
+import type { FileNode } from '@/types/models';
+
+/**
+ * Recursively filter tree to only include folders
+ * @param nodes - Array of FileNode objects
+ * @returns New tree structure with only folder nodes
+ */
+export const filterToFolders = (nodes: FileNode[]): FileNode[] => {
+  return nodes
+    .filter((node) => node.children !== undefined)
+    .map((node) => {
+      const filtered: FileNode = {
+        id: node.id,
+        name: node.name,
+        path: node.path,
+      };
+      if (node.children) {
+        filtered.children = filterToFolders(node.children);
+      }
+      return filtered;
+    });
+};
+
+/**
+ * Find a specific folder node by its path
+ * @param nodes - Array of FileNode objects
+ * @param path - Path to search for
+ * @returns The found FileNode or null
+ */
+export const findFolderByPath = (
+  nodes: FileNode[],
+  path: string
+): FileNode | null => {
+  for (const node of nodes) {
+    if (node.path === path && node.children !== undefined) {
+      return node;
+    }
+    if (node.children) {
+      const found = findFolderByPath(node.children, path);
+      if (found) return found;
+    }
+  }
+  return null;
+};