feat: Implement core application structure, AI extraction, persistence, and Telegram bot modules with updated configuration and dependencies.

app/preprocessing/normalize_text.py

@@ -0,0 +1,11 @@
+"""
+Text normalization functions.
+"""
+
+def normalize_text(text: str) -> str:
+    """
+    Normalizes a string by converting it to lowercase and stripping whitespace.
+    """
+    if not text:
+        return ""
+    return text.lower().strip()