scaffold-ios: scheme references a test plan file that is never generated

[farazbukhari98]

Summary

scaffold-ios generates a shared scheme whose <TestPlans> section references container:<Name>.xctestplan, but that file is never generated. Running tests fails with: Tests cannot be run because the test plan "<Name>" could not be read.

Environment

• xcodebuildmcp 2.6.0
• Xcode 26.4 (Build 17E192)
• macOS 26.4.1

Reproduction

1. Scaffold a project:

xcodebuildmcp project-scaffolding scaffold-ios --project-name SmokeTest --output-path /tmp/smoke --bundle-identifier com.example.smoke

2. (Apply the missing-package-reference fix from the other scaffold issue so the project builds.)
3. Run tests:

xcodebuildmcp simulator test --workspace-path /tmp/smoke/SmokeTest.xcworkspace --scheme SmokeTest --simulator-name "iPhone 17 Pro"

Expected

Tests run. The scheme's test action should use the test plan that does exist (<Name>/<Name>.xctestplan, which is generated and contains both the package test target and the UI test target).

Actual

Errors (1):
  ✗ Failed to build workspace SmokeTest with scheme SmokeTest.: Tests cannot be run because the test plan "SmokeTest" could not be read.

Diagnosis

The generated scheme (<Name>.xcodeproj/xcshareddata/xcschemes/<Name>.xcscheme) contains two TestPlanReference entries:

• container:<Name>.xctestplan — not generated, causes the failure
• container:<Name>/<Name>.xctestplan — generated, marked default = "YES"

Xcode refuses to run the test action while any referenced plan is unreadable.

Fix (verified on 2.6.0)

Remove the dangling TestPlanReference for container:<Name>.xctestplan, keeping only the existing <Name>/<Name>.xctestplan entry. After this, the test run succeeds: 3 tests discovered and passing (2 Swift Testing package tests + 1 UI test), with a readable .xcresult.