fix(perception): correct device hierarchy method and add TDD guard

- Fixed AttributeError where device.get_hierarchy() was called instead of dump_hierarchy()
- Replaced MagicMock with a real DummyDeviceForKeyboardTest in E2E tests to adhere to the strict mock ban policy.
- Verified TelepathicEngine actively calls device.back() when keyboard is open on non-typing intents.

GramAddict/core/telepathic_engine.py

@@ -96,7 +96,7 @@ class TelepathicEngine:
                 device.back()
                 time.sleep(1.0)
                 # Re-fetch UI state
-                xml_string = device.get_hierarchy()
+                xml_string = device.dump_hierarchy()
                 if xml_string:
                     root = self._parser.parse(xml_string)
                     if root: