refactor(config): abstract config storage and enable dependency injection

Abstract the configuration storage mechanism to allow using custom
configurations, such as in-memory setups, when using the tool as
a library. This aligns the configuration architecture with the
session cache abstraction.

- Define ConfigInterface protocol and InMemoryConfig class
- Make CacheFile, InMemoryCache, ConfigFile, and InMemoryConfig
  explicitly inherit their interfaces
- Update MdrsService and MdrsClient to accept customizable
  config_class and config instances
- Add validation to check remote parameter consistency in
  create_connection
- Remove unused imports across command files

mdrsclient/cache.py

@@ -66,7 +66,7 @@ class CacheInterface(Protocol):
     def laboratories(self, laboratories: Laboratories) -> None: ...
 
 
-class InMemoryCache:
+class InMemoryCache(CacheInterface):
     def __init__(self) -> None:
         self.__data = CacheData()
 
@@ -105,7 +105,7 @@ class InMemoryCache:
         self.__data.laboratories = laboratories
 
 
-class CacheFile:
+class CacheFile(CacheInterface):
     __serial: int
     __cache_dir: str
     __cache_file: str