Wipe pulse outputs on graph reset

[pianostringquartet]

resolves https://github.com/StitchDesign/Stitch--Old/issues/7463
resolves https://github.com/StitchDesign/Stitch--Old/issues/7462
resolves https://github.com/StitchDesign/Stitch--Old/issues/7452

[claude]

Code Review for PR #1635: Wipe pulse outputs on graph reset

Summary

This PR addresses pulse output handling during graph resets, specifically targeting issues with pulse values persisting when they shouldn't. The changes are focused and minimal, which is good.

Code Quality & Best Practices

PortValuesUtils.swift

• ✅ Good defensive programming by adding safe array access
• ⚠️ Commented code: Line 124 has commented-out code that should be removed
• ✅ The safe array access pattern prevents potential crashes from index out of bounds

NodeRowObserverSchemaObserverIdentifiable.swift

• ⚠️ Multiple commented code blocks: Lines 95-98 and 100-103 contain commented alternatives that should be removed before merging
• ✅ Good use of optional chaining with getPulse.isDefined
• 📝 TODO comment: Line 101 contains a TODO that should be tracked or resolved

Potential Issues

1. Silent failures: In PortValuesUtils.swift, when output[safe: loopIndex] returns nil, the value is silently skipped. Consider whether this should log a warning or be handled differently.

2. Incomplete solution: The TODO comment suggests uncertainty about whether only pulse-based resets are sufficient. This could lead to edge cases where non-pulse outputs need resetting.

Performance Considerations

• ✅ The changes are minimal and shouldn't introduce performance issues
• ✅ Using first? for checking pulse presence is efficient

Security Concerns

• ✅ No security issues identified
• ✅ Safe array access prevents potential crashes

Test Coverage

• ❌ Missing tests: No test changes included for the new behavior
• Consider adding tests for:
  • Safe array access behavior in PortValuesUtils
  • Pulse output reset behavior
  • Edge cases where loopIndex might be out of bounds

Recommendations

1. Clean up commented code before merging
2. Address the TODO: Either implement a more comprehensive solution or document why pulse-only reset is sufficient
3. Add unit tests for the new safe array access behavior
4. Consider logging: Add debug logging when array access fails to help diagnose issues
5. Document the behavior: Add inline documentation explaining why pulse outputs specifically need to be reset

Questions for Clarification

• What specific scenarios led to issues #7462, #7463, and #7452?
• Are there any other output types besides pulses that might need similar handling?
• Should the safe array access pattern be applied elsewhere in the codebase for consistency?

Overall, this is a focused fix that addresses the immediate issue, but would benefit from cleanup and additional test coverage before merging.