fix: address review feedback on PR #106

- Replace interface{} with any in github/reviews.go (Go 1.18+ idiom)
- Add default panic case to VCS client init switch
- Refactor supersedeOldReviews to return error instead of os.Exit(1)
- Remove spurious blank lines in formatter.go and formatter_test.go
- Add doc comment to DeleteReview explaining when to use vs DismissReview
- Sanitize extractSentinelName output to prevent log injection

review/formatter_test.go

@@ -98,7 +98,6 @@ func TestFormatMarkdown_SpecialChars(t *testing.T) {
 	}
 }
 
-
 func TestFormatMarkdown_Sentinel(t *testing.T) {
 	result := &ReviewResult{
 		Verdict:        "APPROVE",