tests: improve aliasing tests for strict type aliases

tests/aliasing/chan.jule

@@ -0,0 +1,21 @@
+// Copyright 2025 The Jule Programming Language.
+// Use of this source code is governed by a BSD 3-Clause
+// license that can be found in the LICENSE file.
+
+type Chan: chan int
+
+impl Bla2 for Chan {
+	fn foo2(self) {
+		i := <-self
+		if i != 90 {
+			panic("expected 90")
+		}
+	}
+}
+
+fn init() {
+	a := make(Chan, 1)
+	a <- 90
+	m := Bla2(a)
+	m.foo2()
+}

tests/aliasing/map.jule

@@ -0,0 +1,22 @@
+// Copyright 2025 The Jule Programming Language.
+// Use of this source code is governed by a BSD 3-Clause
+// license that can be found in the LICENSE file.
+
+use "std/fmt"
+
+type Map: map[int]str
+
+impl Bla2 for Map {
+	fn foo2(self) {
+		s := fmt::Format("{}", self)
+		if s != "{}" {
+			panic("expected {}")
+		}
+	}
+}
+
+fn init() {
+	a := Map{}
+	m := Bla2(a)
+	m.foo2()
+}