Fix _coconut_partial.__new__ clashing with func= keyword argument

The __new__ method used `func` as a named parameter, which caused
TypeError when user code passed `func` as a keyword argument (e.g.,
f$(func=1) compiling to _coconut_partial(f, func=1)). Changed to
*args/**kwargs and access self.func after construction instead.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: evhub

coconut/root.py

@@ -79,9 +79,9 @@ def wrap(new_func):
 exec("_coconut_exec = exec")
 class _coconut_partial(_coconut_functools.partial):
     __slots__ = ()
-    def __new__(cls, func, *args, **kwargs):
-        self = _coconut_functools.partial.__new__(cls, func, *args, **kwargs)
-        self.__name__ = _coconut.getattr(func, "__name__", None)
+    def __new__(cls, *args, **kwargs):
+        self = _coconut_functools.partial.__new__(cls, *args, **kwargs)
+        self.__name__ = _coconut.getattr(self.func, "__name__", None)
         return self
     def __get__(self, obj, objtype=None):
         if obj is None:
@@ -108,9 +108,9 @@ def __repr__(self):
 from io import open
 class _coconut_partial(_coconut_functools.partial):
     __slots__ = ()
-    def __new__(cls, func, *args, **kwargs):
-        self = _coconut_functools.partial.__new__(cls, func, *args, **kwargs)
-        self.__name__ = _coconut.getattr(func, "__name__", None)
+    def __new__(cls, *args, **kwargs):
+        self = _coconut_functools.partial.__new__(cls, *args, **kwargs)
+        self.__name__ = _coconut.getattr(self.func, "__name__", None)
         return self
     def __get__(self, obj, objtype=None):
         if obj is None: