fix: logo 右半部分从 CODING 改为 CODE

去掉难以正确渲染的 N 和 G 字母，右半部分简化为 CODE（4 字母），
与左半部分 AIR 组合为 AIR CODE。

packages/storybook/.storybook/mocks/app/context/file.ts

@@ -0,0 +1,47 @@
+export type FileSelection = {
+  startLine: number
+  startChar: number
+  endLine: number
+  endChar: number
+}
+
+export type SelectedLineRange = {
+  start: number
+  end: number
+}
+
+export function selectionFromLines(selection?: SelectedLineRange): FileSelection | undefined {
+  if (!selection) return undefined
+  return {
+    startLine: selection.start,
+    startChar: 0,
+    endLine: selection.end,
+    endChar: 0,
+  }
+}
+
+const pool = [
+  "src/session/timeline.tsx",
+  "src/session/composer.tsx",
+  "src/components/prompt-input.tsx",
+  "src/components/session-todo-dock.tsx",
+  "README.md",
+]
+
+export function useFile() {
+  return {
+    tab(path: string) {
+      return `file:${path}`
+    },
+    pathFromTab(tab: string) {
+      if (!tab.startsWith("file:")) return ""
+      return tab.slice(5)
+    },
+    load: async () => undefined,
+    async searchFilesAndDirectories(query: string) {
+      const text = query.trim().toLowerCase()
+      if (!text) return pool
+      return pool.filter((path) => path.toLowerCase().includes(text))
+    },
+  }
+}