feat: add stdin input handling and logging helpers

internal/log/log.go

@@ -0,0 +1,8 @@
+package log
+
+import "fmt"
+
+// Error prints an error message to the user.
+func Error(message string) {
+	fmt.Println("Error:", message)
+}

internal/stdin/stdin.go

@@ -0,0 +1,36 @@
+package stdin
+
+import (
+	"bufio"
+	"io"
+	"os"
+	"strings"
+)
+
+// Read reads input from an stdin pipe.
+func Read() (string, error) {
+	stat, err := os.Stdin.Stat()
+	if err != nil {
+		return "", err
+	}
+
+	if stat.Mode()&os.ModeNamedPipe == 0 && stat.Size() == 0 {
+		return "", nil
+	}
+
+	reader := bufio.NewReader(os.Stdin)
+	var b strings.Builder
+
+	for {
+		r, _, err := reader.ReadRune()
+		if err != nil && err == io.EOF {
+			break
+		}
+		_, err = b.WriteRune(r)
+		if err != nil {
+			return "", err
+		}
+	}
+
+	return b.String(), nil
+}