fix: update task tests to use session_lifespan parameter

ROOT CAUSE:
The experimental task tests were using the old 'lifespan' parameter
which was renamed to 'session_lifespan' in the lifespan redesign.

CHANGES:
- Updated tests/experimental/tasks/server/test_integration.py
- Updated tests/experimental/tasks/client/test_tasks.py
- Changed Server() calls from lifespan= to session_lifespan=

IMPACT:
- Fixes test failures in experimental/tasks/ directory
- All 217 task tests now pass

Github-Issue:#2113

Author: peter-luminova

tests/experimental/tasks/client/test_tasks.py

@@ -102,7 +102,7 @@ async def handle_get_task(ctx: ServerRequestContext[AppContext], params: GetTask
 
     server: Server[AppContext] = Server(
         "test-server",
-        lifespan=_make_lifespan(store, task_done_events),
+        session_lifespan=_make_lifespan(store, task_done_events),
         on_list_tools=_handle_list_tools,
         on_call_tool=_handle_call_tool_with_done_event,
     )
@@ -153,7 +153,7 @@ async def handle_get_task_result(
 
     server: Server[AppContext] = Server(
         "test-server",
-        lifespan=_make_lifespan(store, task_done_events),
+        session_lifespan=_make_lifespan(store, task_done_events),
         on_list_tools=_handle_list_tools,
         on_call_tool=handle_call_tool,
     )
@@ -200,7 +200,7 @@ async def handle_list_tasks(
 
     server: Server[AppContext] = Server(
         "test-server",
-        lifespan=_make_lifespan(store, task_done_events),
+        session_lifespan=_make_lifespan(store, task_done_events),
         on_list_tools=_handle_list_tools,
         on_call_tool=_handle_call_tool_with_done_event,
     )
@@ -277,7 +277,7 @@ async def handle_cancel_task(
 
     server: Server[AppContext] = Server(
         "test-server",
-        lifespan=_make_lifespan(store, task_done_events),
+        session_lifespan=_make_lifespan(store, task_done_events),
         on_list_tools=_handle_list_tools,
         on_call_tool=handle_call_tool_no_work,
     )

tests/experimental/tasks/server/test_integration.py

@@ -123,7 +123,7 @@ async def handle_list_tasks(
 
     server: Server[AppContext] = Server(
         "test-tasks",
-        lifespan=_make_lifespan(store, task_done_events),
+        session_lifespan=_make_lifespan(store, task_done_events),
         on_list_tools=handle_list_tools,
         on_call_tool=handle_call_tool,
     )
@@ -216,7 +216,7 @@ async def handle_get_task(ctx: ServerRequestContext[AppContext], params: GetTask
 
     server: Server[AppContext] = Server(
         "test-tasks-failure",
-        lifespan=_make_lifespan(store, task_done_events),
+        session_lifespan=_make_lifespan(store, task_done_events),
         on_list_tools=handle_list_tools,
         on_call_tool=handle_call_tool,
     )