docs: fix README plan scope check

docs/superpowers/plans/2026-08-04-em-planner-readme-implementation.md

@@ -34,8 +34,10 @@
 从仓库根目录运行：
 
 ```powershell
-Select-String -Path ClumsyPilot/ParkrobTrajplanner/EMPlanner/README.md -Encoding UTF8 `
-  -Pattern '尚未实现 LS 横向优化、ST 纵向优化、滚动协调、轨迹发布'
+$text = Get-Content ClumsyPilot/ParkrobTrajplanner/EMPlanner/README.md -Raw -Encoding UTF8
+if ($text -notmatch '尚未实现 LS 横向优化、\s*ST 纵向优化、滚动协调、轨迹发布') {
+  throw 'Expected the stale Foundation-only scope marker.'
+}
 ```
 
 Expected: 找到一条 Foundation 阶段的旧描述，证明重写前 README 与当前实现不一致。
@@ -79,7 +81,7 @@ $required = @(
 foreach ($item in $required) {
   if (-not $text.Contains($item)) { throw "Missing README contract: $item" }
 }
-if ($text.Contains('尚未实现 LS 横向优化、ST 纵向优化、滚动协调、轨迹发布')) {
+if ($text -match '尚未实现 LS 横向优化、\s*ST 纵向优化、滚动协调、轨迹发布') {
   throw 'Stale Foundation-only scope remains.'
 }
 ```