Initialize Article Data Manager project

src/article_data_manager/validation/article_number.py

@@ -0,0 +1,12 @@
+"""Article number normalization."""
+
+
+def normalize_article_number(value: str) -> str:
+    """Trim surrounding whitespace while preserving leading zeros and text content."""
+
+    if not isinstance(value, str):
+        raise TypeError("Article number must be provided as a string.")
+    normalized = value.strip()
+    if normalized == "":
+        raise ValueError("Article number must not be empty.")
+    return normalized