fix: annotate redis_client param and formalize Args in RedisCredentialStore.__init__; refresh MCP docs

mail_intake/credentials/redis.py

@@ -25,7 +25,7 @@ responsibility of authentication provider implementations.
 """
 
 from collections.abc import Callable
-from typing import TypeVar
+from typing import Any, TypeVar
 
 from mail_intake.credentials.store import CredentialStore
 
@@ -57,7 +57,7 @@ class RedisCredentialStore(CredentialStore[T]):
 
     def __init__(
         self,
-        redis_client,
+        redis_client: Any,
         key: str,
         serialize: Callable[[T], bytes],
         deserialize: Callable[[bytes], T],
@@ -66,10 +66,18 @@ class RedisCredentialStore(CredentialStore[T]):
         """
         Initialize a Redis-backed credential store.
 
-        Callers supply all runtime dependencies: ``redis_client`` is an
-        initialized Redis client instance, ``key`` names the storage key,
-        ``serialize``/``deserialize`` are the encoding and decoding callables,
-        and ``ttl_seconds`` optionally limits credential lifetime.
+        Args:
+            redis_client (Any):
+                Initialized Redis client instance used for persistence.
+            key (str):
+                Storage key under which credentials are persisted.
+            serialize (Callable[[T], bytes]):
+                Callable that encodes credentials to bytes for storage.
+            deserialize (Callable[[bytes], T]):
+                Callable that decodes stored bytes back into credentials.
+            ttl_seconds (int | None):
+                Optional time-to-live in seconds after which stored
+                credentials expire automatically. ``None`` disables expiry.
         """
         self.redis = redis_client
         self.key = key