Drop int() delegation to __trunc__ (#7703)

CPython 3.14 fully removed the long-deprecated fallback from int() to
__trunc__. Classes that want int(x) support must implement __int__ or
__index__; math.trunc(x) continues to use __trunc__.

Delete the __trunc__ branch in PyObject::try_int so a class with only
__trunc__ now reaches the existing TypeError arm, matching CPython.

Unmasks test_int.IntTestCases.test_intconversion.

Lib/test/test_int.py

@@ -380,7 +380,6 @@ class IntTestCases(unittest.TestCase):
     def test_string_float(self):
         self.assertRaises(ValueError, int, '1.2')
 
-    @unittest.expectedFailure  # TODO: RUSTPYTHON; AssertionError: TypeError not raised
     def test_intconversion(self):
         # Test __int__()
         class ClassicMissingMethods:

crates/vm/src/protocol/number.rs

@@ -58,20 +58,6 @@ impl PyObject {
             Ok(i.to_owned())
         } else if let Some(i) = self.number().int(vm).or_else(|| self.try_index_opt(vm)) {
             i
-        } else if let Ok(Some(f)) = vm.get_special_method(self, identifier!(vm, __trunc__)) {
-            _warnings::warn(
-                vm.ctx.exceptions.deprecation_warning,
-                "The delegation of int() to __trunc__ is deprecated.".to_owned(),
-                1,
-                vm,
-            )?;
-            let ret = f.invoke((), vm)?;
-            ret.try_index(vm).map_err(|_| {
-                vm.new_type_error(format!(
-                    "__trunc__ returned non-Integral (type {})",
-                    ret.class()
-                ))
-            })
         } else if let Some(s) = self.downcast_ref::<PyStr>() {
             try_convert(self, s.as_wtf8().trim().as_bytes(), vm)
         } else if let Some(bytes) = self.downcast_ref::<PyBytes>() {