Update project structure and documentation: Add new entries to .gitignore for standalone outputs and MCP config, delete obsolete design_skill.md file, and revise README and various skills to reflect updated workflow steps, including UI design and performance testing. Adjust paths in retrospective and metrics documentation to align with new directory structure.

.cursor/agents/implementer.md

@@ -4,6 +4,8 @@ description: |
   Implements a single task from its spec file. Use when implementing tasks from _docs/02_tasks/.
   Reads the task spec, analyzes the codebase, implements the feature with tests, and verifies acceptance criteria.
   Launched by the /implement skill as a subagent.
+category: build
+tags: [implementation, subagent, task-execution, testing, code-generation]
 ---
 
 You are a professional software developer implementing a single task.
@@ -56,7 +58,7 @@ Load context in this order, stopping when you have enough:
 4. If the task has a dependency on an unimplemented component, create a minimal interface mock
 5. Implement the feature following existing code conventions
 6. Implement error handling per the project's defined strategy
-7. Implement unit tests (use //Arrange //Act //Assert comments)
+7. Implement unit tests following Arrange/Act/Assert (AAA) pattern — mark each section with a comment in the current language's style (e.g., `// Arrange` in C#/Rust/JS, `# Arrange` in Python, `-- Arrange` in SQL)
 8. Implement integration tests — analyze existing tests, add to them or create new
 9. Run all tests, fix any failures
 10. Verify every acceptance criterion is satisfied — trace each AC with evidence