fix(scoring): normalize ∞ and \infty to the same token

pyproject.toml

@@ -18,7 +18,7 @@ dependencies = [
 ]
 
 [project.optional-dependencies]
-dev = ["pytest>=8.0", "ruff>=0.5", "mypy>=1.10"]
+dev = ["pytest>=8.0", "ruff>=0.5,<0.16", "mypy>=1.10"]
 
 [build-system]
 requires = ["hatchling"]

src/trinity/adapters/drop.py

@@ -132,7 +132,7 @@ def _maybe_unbox(segment: str) -> str:
 
 #: Surrounding punctuation stripped from a token, EXCLUDING the signs ``+``/``-`` — a
 #: leading sign is part of a number's value, not wrapping noise.
-_STRIP_EDGE = "".join(c for c in string.punctuation if c not in "+-")
+_STRIP_EDGE = "".join(c for c in string.punctuation if c not in "+-.")
 
 
 def _normalize_token(raw: str) -> str:
@@ -157,10 +157,12 @@ def _normalize_token(raw: str) -> str:
     except ValueError:
         pass
     core = raw.strip(_STRIP_EDGE)
-    try:
-        return str(float(core.replace(",", "")))
-    except ValueError:
-        return _PUNCT.sub("", raw)
+    for cand in (core, core.rstrip(".")):
+        try:
+            return str(float(cand.replace(",", "")))
+        except ValueError:
+            continue
+    return _PUNCT.sub("", raw)
 
 
 def _split_internal_hyphens(token: str) -> list[str]:

src/trinity/orchestration/reward.py

@@ -842,6 +842,8 @@ def normalize_math_answer(ans: str | None) -> str:
     # (the product symbol) is intentionally left untouched.
     s = re.sub(r"\\pi(?![a-zA-Z])", "pi", s)
     s = s.replace("π", "pi")
+    s = s.replace("∞", "oo")
+    s = re.sub(r"\\infty(?![a-zA-Z])", "oo", s)
     # The fraction normalizer wraps arbitrary operands, so ``\frac{\pi}{2}``
     # becomes ``(pi)/(2)`` while ``\pi/2`` becomes ``pi/2``. Remove only
     # standalone atomic operands adjacent to division — including a lone