fix: normalize Windows extended-length store paths

On a Windows runner pnpm 12 reports a store path like
`\\?\D:\.pnpm-store\v11`, and the post step then fails with
"Invalid pattern. Root segment must not contain globs" — the cache toolkit
reads the `?` in that prefix as a glob in the root segment. Cache APIs do not
need the extended-length form, so the path is converted back to a regular
drive or UNC path, the same way pnpm/setup handles it.

Reported in pnpm/action-setup#286 and reproduced by the Windows leg of the
lockfile verification cache job.

src/cache-restore/run.ts

@@ -5,6 +5,7 @@ import { hashFiles } from '@actions/glob'
 import os from 'os'
 import { Inputs } from '../inputs'
 import { restoreVerificationCache } from '../lockfile-verification-cache'
+import { removeWindowsExtendedPathPrefix } from '../windows-path'
 
 export async function runRestoreCache(inputs: Inputs) {
   const fileHash = await hashFiles(inputs.cacheDependencyPath)
@@ -48,7 +49,7 @@ async function runRestoreStoreCache(fileHash: string) {
 
 async function getCacheDirectory() {
   const { stdout } = await getExecOutput('pnpm store path --silent')
-  const cacheFolderPath = stdout.trim()
+  const cacheFolderPath = removeWindowsExtendedPathPrefix(stdout.trim())
   debug(`Cache folder is set to "${cacheFolderPath}"`)
   return cacheFolderPath
 }