Associate crashes with last started test

[alexey1312]

Description

• Track Test Case '...' started. lines to associate crashes (SIGTRAP, SIGABRT, Fatal error) with the specific test that caused them
• Previously, when a test crashed on assert()/precondition(), xcsift reported failed_tests: 0 with a generic error — making it impossible for AI agents or developers to identify which test failed
• Three-level crash detection:
  • Restarting after... with signal code creates a FailedTest entry with signal info
  • Fatal error with a tracked started test creates a FailedTest with file/line from the error
  • Safety net: if a test started but never completed and TEST FAILED appears, a FailedTest is created at end-of-parse
• Supports both XCTest (Test Case '...' started.) and Swift Testing (◇ Test "..." started.) formats
• lastStartedTestName is correctly cleared on passed or failed to prevent false associations

Additional notes

• 8 new tests + 1 updated existing test covering all crash association scenarios
• All 286 tests pass with zero regressions

[Copilot]

Pull request overview

Updates the OutputParser to associate crash indicators in xcodebuild output (signal exits and fatal errors) with the most recently started test, so failedTests is populated with actionable per-test failures instead of only generic run-level failure state.

Changes:

• Track the last started test name and signal code while parsing output, and create FailedTest entries on crash confirmation / fatal error.
• Add an end-of-parse “safety net” to emit a FailedTest when a test started but never completed and the run failed.
• Expand ParsingTests to cover crash association scenarios for both XCTest and Swift Testing formats.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
Sources/OutputParser.swift	Adds crash association state + parsing logic to map crashes/fatal errors to the last started test.
Tests/ParsingTests.swift	Adds test coverage for signal crashes, fatal errors, Swift Testing started format, and safety-net behavior.

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[Copilot]

The new containsRelevant filter checks line.contains("' started") / line.contains("\" started"), which will also mark unrelated lines like Test Suite '...' started at ... as relevant. That defeats the purpose of this fast-path (it forces the parser to run the more expensive parsing chain on many suite-start lines) and could regress performance on large logs. Consider tightening these conditions to the specific formats you actually parse (e.g., hasPrefix("Test Case '") || hasPrefix("Test case '") || hasPrefix("◇ Test ")) rather than substring matches.

Suggested change

	|| line.contains("' started") // XCTest: "Test Case '...' started."
	|| line.contains("\" started") // Swift Testing: Test "..." started
	|| line.contains("signal code ") // "Exited with [unexpected] signal code N"
	|| line.hasPrefix("Restarting after") // crash confirmation
	|| line.hasPrefix("Test Case '") // XCTest: "Test Case '...' started."
	|| line.hasPrefix("Test case '") // variant casing
	|| line.hasPrefix("◇ Test ") // Swift Testing formatted tests
	|| line.hasPrefix("Test \"") // Swift Testing: Test "..." started
	|| line.contains("signal code ") // "Exited with [unexpected] signal code N"
	|| line.hasPrefix("Restarting after") // crash confirmation