fix: resolve golangci-lint errors

- Add error check for fmt.Fprintf in tips.go (errcheck)
- Add nolint for safe SQL formatting in transaction.go (gosec G201)
- Fix 'cancelled' -> 'canceled' spelling (misspell)

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Co-Authored-By: Claude <noreply@anthropic.com>

cmd/bd/tips.go

@@ -73,7 +73,7 @@ func maybeShowTip(store storage.Storage) {
 	}
 
 	// Display tip to stdout (informational, not an error)
-	fmt.Fprintf(os.Stdout, "\n💡 Tip: %s\n", tip.Message)
+	_, _ = fmt.Fprintf(os.Stdout, "\n💡 Tip: %s\n", tip.Message)
 
 	// Record that we showed this tip
 	recordTipShown(store, tip.ID)