Add comprehensive KeyValue test coverage and fix KVConfig type stubs

Co-authored-by: s3rius <18153319+s3rius@users.noreply.github.com>
Agent-Logs-Url: https://github.com/taskiq-python/natsrpy/sessions/ee16d7cc-5cf8-4996-9622-78eb546b14b2

Author: Copilot

python/natsrpy/_natsrpy_rs/js/kv.pyi

@@ -75,7 +75,7 @@ class KVConfig:
     description: str
     max_value_size: int | None
     history: int | None
-    max_age: float | None
+    max_age: timedelta | None
     max_bytes: int | None
     storage: StorageType | None
     num_replicas: int | None
@@ -85,15 +85,15 @@ class KVConfig:
     mirror_direct: bool | None
     compression: bool | None
     placement: Placement | None
-    limit_markers: float | None
+    limit_markers: timedelta | None
 
     def __new__(
         cls,
         bucket: str,
         description: str | None = None,
         max_value_size: int | None = None,
         history: int | None = None,
-        max_age: float | None = None,
+        max_age: timedelta | None = None,
         max_bytes: int | None = None,
         storage: StorageType | None = None,
         num_replicas: int | None = None,
@@ -103,7 +103,7 @@ class KVConfig:
         mirror_direct: bool | None = None,
         compression: bool | None = None,
         placement: Placement | None = None,
-        limit_markers: float | None = None,
+        limit_markers: timedelta | None = None,
     ) -> Self: ...
 
 @final