fix: resolve all remaining test failures

Root cause: extractInboundTaskContext tried to create a RequestTaskStore
even when the Protocol had no taskStore configured (client-side). When a
client received a task-related elicitation request, the store creation
threw, silently breaking the handler response flow.

Fix: Only create taskContext (with RequestTaskStore) when _taskStore is
configured. Clients receiving task-related requests (elicitation, sampling)
still get relatedTaskId for metadata propagation but don't get a taskStore.

Also:
- Fix McpServer handleAutomaticTaskPolling to construct JSONRPCRequest for
  createRequestTaskStore
- Remove debug logging

Results:
- Core: 430/430 pass
- Integration: 487/487 pass
- Type errors: 0

Author: felixweinberger

packages/core/src/shared/taskManager.ts

@@ -457,14 +457,17 @@ export class TaskManager {
             return {};
         }
 
-        const taskStore = this.createRequestTaskStore(request, sessionId);
-
-        // Create task context if there's a related task ID or task creation params
-        const taskContext: TaskContext | undefined = (relatedTaskId || taskCreationParams) ? {
-            taskId: relatedTaskId ?? '',
-            taskStore,
-            requestedTtl: taskCreationParams?.ttl
-        } : undefined;
+        // Only create task context if we have a task store (server-side)
+        // Clients may receive task-related requests (e.g., elicitation) without having a task store
+        let taskContext: TaskContext | undefined;
+        if (this._taskStore && (relatedTaskId || taskCreationParams)) {
+            const taskStore = this.createRequestTaskStore(request, sessionId);
+            taskContext = {
+                taskId: relatedTaskId ?? '',
+                taskStore,
+                requestedTtl: taskCreationParams?.ttl
+            };
+        }
 
         return {
             relatedTaskId,