Update assistant features and docs

app/core/roman.py

@@ -0,0 +1,43 @@
+"""Roman numeral parsing helpers."""
+
+import re
+
+_ROMAN_VALID_RE = re.compile(
+    r"^M{0,3}(CM|CD|D?C{0,3})"
+    r"(XC|XL|L?X{0,3})"
+    r"(IX|IV|V?I{0,3})$"
+)
+_ROMAN_TOKEN_RE = re.compile(r"(?<![A-Za-zА-Яа-яЁё0-9])[IVXLCDMivxlcdm]+(?![A-Za-zА-Яа-яЁё0-9])")
+_ROMAN_VALUES = {"I": 1, "V": 5, "X": 10, "L": 50, "C": 100, "D": 500, "M": 1000}
+
+
+def roman_to_int(token: str) -> int | None:
+    if not token:
+        return None
+
+    roman = token.strip().upper()
+    if not roman or not _ROMAN_VALID_RE.fullmatch(roman):
+        return None
+
+    total = 0
+    prev = 0
+    for char in reversed(roman):
+        value = _ROMAN_VALUES[char]
+        if value < prev:
+            total -= value
+        else:
+            total += value
+            prev = value
+    return total
+
+
+def replace_roman_numerals(text: str) -> str:
+    if not text:
+        return text
+
+    def _repl(match: re.Match) -> str:
+        token = match.group(0)
+        value = roman_to_int(token)
+        return str(value) if value is not None else token
+
+    return _ROMAN_TOKEN_RE.sub(_repl, text)