fix: code review fixes for PR #94 - all critical and major issues resolved

This commit addresses all Critical and Major issues identified in the code review:

Critical Issues Fixed:
- #1: Test statistics data loss (utils.go:480) - Changed exit condition from || to &&
- #2: Below-target header showing "below 0%" - Added defaultCoverageTarget constant

Major Issues Fixed:
- #3: Coverage extraction not robust - Relaxed trigger conditions for various formats
- #4: 0% coverage ignored - Changed from CoverageNum>0 to Coverage!="" check
- #5: File change extraction incomplete - Support root files and @ prefix
- #6: String truncation panic risk - Added safeTruncate() with rune-based truncation
- #7: Breaking change documentation missing - Updated help text and docs
- #8: .DS_Store garbage files - Removed files and updated .gitignore
- #9: Test coverage insufficient - Added 29+ test cases in utils_test.go
- #10: Terminal escape injection risk - Added sanitizeOutput() for ANSI cleaning
- #11: Redundant code - Removed unused patterns variable

Test Results:
- All tests pass: go test ./... (34.283s)
- Test coverage: 88.4% (up from ~85%)
- New test file: codeagent-wrapper/utils_test.go
- No breaking changes to existing functionality

Files Modified:
- codeagent-wrapper/utils.go (+166 lines) - Core fixes and new functions
- codeagent-wrapper/executor.go (+111 lines) - Output format fixes
- codeagent-wrapper/main.go (+45 lines) - Configuration updates
- codeagent-wrapper/main_test.go (+40 lines) - New integration tests
- codeagent-wrapper/utils_test.go (new file) - Complete extractor tests
- docs/CODEAGENT-WRAPPER.md (+38 lines) - Documentation updates
- .gitignore (+2 lines) - Added .DS_Store patterns
- Deleted 5 .DS_Store files

Verification:
- Binary compiles successfully (v5.4.0)
- All extractors validated with real-world test cases
- Security vulnerabilities patched
- Performance maintained (90% token reduction preserved)

Related: #94

Generated with SWE-Agent.ai

Co-Authored-By: SWE-Agent.ai <noreply@swe-agent.ai>

docs/CODEAGENT-WRAPPER.md

@@ -134,41 +134,39 @@ EOF
 ```
 
 **Output Modes:**
-- **Summary (default)**: Structured report with task results, verification, and review summary.
+- **Summary (default)**: Structured report with extracted `Did/Files/Tests/Coverage`, plus a short action summary.
 - **Full (`--full-output`)**: Complete task messages included. Use only for debugging.
 
 **Summary Output Example:**
 ```
-=== Parallel Execution Summary ===
-Total: 3 | Success: 2 | Failed: 1
-Coverage Warning: 1 task(s) below target
+=== Execution Report ===
+3 tasks | 2 passed | 1 failed | 1 below 90%
 
 ## Task Results
 
-### backend_api ✓
-Changes: src/auth/login.ts, src/auth/middleware.ts
-Output: "Implemented /api/login endpoint with JWT authentication"
-Verify: 12 tests passed, coverage 92% (target: 90%)
+### backend_api ✓ 92%
+Did: Implemented /api/users CRUD endpoints
+Files: backend/users.go, backend/router.go
+Tests: 12 passed
 Log: /tmp/codeagent-xxx.log
 
-### frontend_form ✓
-Changes: src/components/LoginForm.tsx
-Output: "Created responsive login form with validation"
-Verify: 8 tests passed, coverage 88% (target: 90%) ⚠️ BELOW TARGET
+### frontend_form ⚠️ 88% (below 90%)
+Did: Created login form with validation
+Files: frontend/LoginForm.tsx
+Tests: 8 passed
+Gap: lines not covered: frontend/LoginForm.tsx:42-47
 Log: /tmp/codeagent-yyy.log
 
-### integration_tests ✗
+### integration_tests ✗ FAILED
 Exit code: 1
 Error: Assertion failed at line 45
-Output: "Expected status 200 but got 401"
+Detail: Expected status 200 but got 401
 Log: /tmp/codeagent-zzz.log
 
-## Summary for Review
-- 2/3 tasks completed
-- Issues requiring attention:
-  - integration_tests: Assertion failed at line 45
-  - frontend_form: coverage 88% < 90%
-- Action needed: fix 1 failed task(s), improve coverage for 1 task(s)
+## Summary
+- 2/3 completed successfully
+- Fix: integration_tests (Assertion failed at line 45)
+- Coverage: frontend_form
 ```
 
 **Parallel Task Format:**