ref: typehints, enum instead of raw string, abc and other (#1)

Full code coverage with annotations, fixing errors in various linters: ruff, wps, etc. Fixing errors in type checkers: ty, mypy, pyright. Formatting and bringing code to a consistent style, applying best practices in various aspects.

src/argenta/app/protocols.py

@@ -0,0 +1,22 @@
+from typing import Protocol, TypeVar
+
+T = TypeVar('T', contravariant=True) # noqa: WPS111
+
+
+class NonStandardBehaviorHandler(Protocol[T]):
+    def __call__(self, __param: T) -> None:
+        raise NotImplementedError
+    
+class EmptyCommandHandler(Protocol):
+    def __call__(self) -> None:
+        raise NotImplementedError
+        
+
+class Printer(Protocol):
+    def __call__(self, __text: str) -> None:
+        raise NotImplementedError
+
+
+class DescriptionMessageGenerator(Protocol):
+    def __call__(self, __first_param: str, __second_param: str) -> str:
+        raise NotImplementedError