fix: companion 改用 $.fs，修正 hooks 模組載入失敗

node-fs.ts 引用 node:fs/promises，hooks 沙箱不允許，導致 /companion 指令未註冊。
改為以引擎的 $.fs 包成 Fs adapter；rename 改為選用，無 rename 時直接覆寫。
版本號調整為 0.0.1。

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

plugins/companion/hooks/register.tsx

@@ -2,7 +2,7 @@ import type { Register } from 'claude-code'
 
 import { fitCompanion } from './companion/band'
 import { createCompanion } from './companion/core'
-import { nodeFs } from './companion/node-fs'
+import { engineFs } from './companion/engine-fs'
 
 let companion: ReturnType<typeof createCompanion> | undefined
 
@@ -14,7 +14,7 @@ export const register: Register = on => {
       argumentHint: 'status | switch <角色> | off | setup',
     })
     const home = await $.env.get('HOME')
-    companion = createCompanion({ fs: nodeFs, clock: { now: Date.now }, root: `${home ?? ''}/.companion` })
+    companion = createCompanion({ fs: engineFs({ read: p => $.fs.read(p), write: (p, t) => $.fs.write(p, t), list: p => $.fs.list(p) }), clock: { now: Date.now }, root: `${home ?? ''}/.companion` })
     const first = await companion.ensureActivated()
     if (first.first) $.ui.toast(`已啟用 ${first.name}。用 /companion off 可關閉`)