Add Python 3.14 preview (#2390)

* feat: add CPython 3.14 beta 1

* fix tests

noxfile.py

@@ -73,7 +73,7 @@ def update_constraints(session: nox.Session) -> None:
     if session.venv_backend != "uv":
         session.install("uv>=0.1.23")
 
-    for minor_version in range(8, 14):
+    for minor_version in range(8, 15):
         python_version = f"3.{minor_version}"
         env = os.environ.copy()
         # CUSTOM_COMPILE_COMMAND is a pip-compile option that tells users how to
@@ -92,7 +92,7 @@ def update_constraints(session: nox.Session) -> None:
         )
 
     shutil.copyfile(
-        resources / "constraints-python312.txt",
+        resources / "constraints-python314.txt",
         resources / "constraints.txt",
     )