fix: vendor wcf python deps for isolated profile

scripts/windows/personal-wechat/prepare.ps1

@@ -6,6 +6,7 @@ $ExtractRoot = Join-Path $Root "wechat-3.9.12.51-extracted"
 $VersionRoot = Join-Path $ExtractRoot "[3.9.12.51]"
 $DataRoot = Join-Path $Root "data\profile"
 $WcfRoot = Join-Path $Root "wcf\v39.5.2"
+$PythonSite = Join-Path $WcfRoot "python-site"
 $StateRoot = Join-Path $Root "wcf-state"
 $DownloadRoot = Join-Path $Root "downloads"
 $PrepareResult = Join-Path $StateRoot "prepare-result.json"
@@ -15,7 +16,7 @@ $PipIndex = "http://mirrors.aliyun.com/pypi/simple/"
 $ReleaseBase = "https://github.com/lich0821/WeChatFerry/releases/download/v39.5.2"
 $RegistryPath = "HKCU:\Software\Tencent\WeChat"
 
-New-Item -ItemType Directory -Force $WechatRoot,$ExtractRoot,$VersionRoot,$DataRoot,$WcfRoot,$StateRoot,$DownloadRoot | Out-Null
+New-Item -ItemType Directory -Force $WechatRoot,$ExtractRoot,$VersionRoot,$DataRoot,$WcfRoot,$PythonSite,$StateRoot,$DownloadRoot | Out-Null
 $StartedAt = (Get-Date).ToUniversalTime().ToString("o")
 
 function Write-PrepareProgress {
@@ -124,7 +125,7 @@ function Install-Wcferry {
   $pipOut = Join-Path $StateRoot "prepare-pip.stdout.log"
   $pipErr = Join-Path $StateRoot "prepare-pip.stderr.log"
   Write-PrepareProgress "pip-install-start"
-  & $Python -m pip install --trusted-host mirrors.aliyun.com --index-url $PipIndex --timeout 120 --retries 8 "wcferry==39.5.2.0" > $pipOut 2> $pipErr
+  & $Python -m pip install --upgrade --target $PythonSite --trusted-host mirrors.aliyun.com --index-url $PipIndex --timeout 120 --retries 8 "wcferry==39.5.2.0" > $pipOut 2> $pipErr
   if ($LASTEXITCODE -ne 0) { throw "pip install wcferry failed; see $pipErr" }
   Write-PrepareProgress "pip-install-done"
 
@@ -142,7 +143,13 @@ payload = {
 }
 print(json.dumps(payload, ensure_ascii=False))
 '@ | Set-Content -Encoding utf8 $probePy
-  $pyProbe = (& $Python $probePy) | ConvertFrom-Json
+  $oldPythonPath = $env:PYTHONPATH
+  try {
+    $env:PYTHONPATH = if ($oldPythonPath) { "$PythonSite;$oldPythonPath" } else { $PythonSite }
+    $pyProbe = (& $Python $probePy) | ConvertFrom-Json
+  } finally {
+    $env:PYTHONPATH = $oldPythonPath
+  }
   return [ordered]@{
     ok = [bool]$pyProbe.ok
     version = $pyProbe.wcferryVersion
@@ -231,6 +238,7 @@ $summary = [ordered]@{
   requiredVersion = "3.9.12.51"
   profile = $profile
   wcfRoot = $WcfRoot
+  pythonSite = $PythonSite
   stateRoot = $StateRoot
   python = $Python
   wcferryVersion = $wcferry.version