Fix project isolation: Make loadChatHistory respect active project sessions

- Modified loadChatHistory() to check for active project before fetching all sessions
- When active project exists, use project.sessions instead of fetching from API
- Added detailed console logging to debug session filtering
- This prevents ALL sessions from appearing in every project's sidebar

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.venv/lib/python3.11/site-packages/mcp/shared/experimental/tasks/helpers.py

@@ -0,0 +1,181 @@
+"""
+Helper functions for pure task management.
+
+These helpers work with pure TaskContext and don't require server dependencies.
+For server-integrated task helpers, use mcp.server.experimental.
+"""
+
+from collections.abc import AsyncIterator
+from contextlib import asynccontextmanager
+from datetime import datetime, timezone
+from uuid import uuid4
+
+from mcp.shared.exceptions import McpError
+from mcp.shared.experimental.tasks.context import TaskContext
+from mcp.shared.experimental.tasks.store import TaskStore
+from mcp.types import (
+    INVALID_PARAMS,
+    TASK_STATUS_CANCELLED,
+    TASK_STATUS_COMPLETED,
+    TASK_STATUS_FAILED,
+    TASK_STATUS_WORKING,
+    CancelTaskResult,
+    ErrorData,
+    Task,
+    TaskMetadata,
+    TaskStatus,
+)
+
+# Metadata key for model-immediate-response (per MCP spec)
+# Servers MAY include this in CreateTaskResult._meta to provide an immediate
+# response string while the task executes in the background.
+MODEL_IMMEDIATE_RESPONSE_KEY = "io.modelcontextprotocol/model-immediate-response"
+
+# Metadata key for associating requests with a task (per MCP spec)
+RELATED_TASK_METADATA_KEY = "io.modelcontextprotocol/related-task"
+
+
+def is_terminal(status: TaskStatus) -> bool:
+    """
+    Check if a task status represents a terminal state.
+
+    Terminal states are those where the task has finished and will not change.
+
+    Args:
+        status: The task status to check
+
+    Returns:
+        True if the status is terminal (completed, failed, or cancelled)
+    """
+    return status in (TASK_STATUS_COMPLETED, TASK_STATUS_FAILED, TASK_STATUS_CANCELLED)
+
+
+async def cancel_task(
+    store: TaskStore,
+    task_id: str,
+) -> CancelTaskResult:
+    """
+    Cancel a task with spec-compliant validation.
+
+    Per spec: "Receivers MUST reject cancellation of terminal status tasks
+    with -32602 (Invalid params)"
+
+    This helper validates that the task exists and is not in a terminal state
+    before setting it to "cancelled".
+
+    Args:
+        store: The task store
+        task_id: The task identifier to cancel
+
+    Returns:
+        CancelTaskResult with the cancelled task state
+
+    Raises:
+        McpError: With INVALID_PARAMS (-32602) if:
+            - Task does not exist
+            - Task is already in a terminal state (completed, failed, cancelled)
+
+    Example:
+        @server.experimental.cancel_task()
+        async def handle_cancel(request: CancelTaskRequest) -> CancelTaskResult:
+            return await cancel_task(store, request.params.taskId)
+    """
+    task = await store.get_task(task_id)
+    if task is None:
+        raise McpError(
+            ErrorData(
+                code=INVALID_PARAMS,
+                message=f"Task not found: {task_id}",
+            )
+        )
+
+    if is_terminal(task.status):
+        raise McpError(
+            ErrorData(
+                code=INVALID_PARAMS,
+                message=f"Cannot cancel task in terminal state '{task.status}'",
+            )
+        )
+
+    # Update task to cancelled status
+    cancelled_task = await store.update_task(task_id, status=TASK_STATUS_CANCELLED)
+    return CancelTaskResult(**cancelled_task.model_dump())
+
+
+def generate_task_id() -> str:
+    """Generate a unique task ID."""
+    return str(uuid4())
+
+
+def create_task_state(
+    metadata: TaskMetadata,
+    task_id: str | None = None,
+) -> Task:
+    """
+    Create a Task object with initial state.
+
+    This is a helper for TaskStore implementations.
+
+    Args:
+        metadata: Task metadata
+        task_id: Optional task ID (generated if not provided)
+
+    Returns:
+        A new Task in "working" status
+    """
+    now = datetime.now(timezone.utc)
+    return Task(
+        taskId=task_id or generate_task_id(),
+        status=TASK_STATUS_WORKING,
+        createdAt=now,
+        lastUpdatedAt=now,
+        ttl=metadata.ttl,
+        pollInterval=500,  # Default 500ms poll interval
+    )
+
+
+@asynccontextmanager
+async def task_execution(
+    task_id: str,
+    store: TaskStore,
+) -> AsyncIterator[TaskContext]:
+    """
+    Context manager for safe task execution (pure, no server dependencies).
+
+    Loads a task from the store and provides a TaskContext for the work.
+    If an unhandled exception occurs, the task is automatically marked as failed
+    and the exception is suppressed (since the failure is captured in task state).
+
+    This is useful for distributed workers that don't have a server session.
+
+    Args:
+        task_id: The task identifier to execute
+        store: The task store (must be accessible by the worker)
+
+    Yields:
+        TaskContext for updating status and completing/failing the task
+
+    Raises:
+        ValueError: If the task is not found in the store
+
+    Example (distributed worker):
+        async def worker_process(task_id: str):
+            store = RedisTaskStore(redis_url)
+            async with task_execution(task_id, store) as ctx:
+                await ctx.update_status("Working...")
+                result = await do_work()
+                await ctx.complete(result)
+    """
+    task = await store.get_task(task_id)
+    if task is None:
+        raise ValueError(f"Task {task_id} not found")
+
+    ctx = TaskContext(task, store)
+    try:
+        yield ctx
+    except Exception as e:
+        # Auto-fail the task if an exception occurs and task isn't already terminal
+        # Exception is suppressed since failure is captured in task state
+        if not is_terminal(ctx.task.status):
+            await ctx.fail(str(e))
+        # Don't re-raise - the failure is recorded in task state