feat(KB-503): add multi-project CLI support with project subcommands

- Add project subcommands: list, add, remove, show, set-default, detect
- Add --project flag support for all task commands
- Create project-context.ts utilities for project resolution
- Add defaultProjectId to GlobalSettings type
- Implement project auto-detection from cwd
- Update CLI argument parsing for global --project flag
- Add multi-project CLI documentation to AGENTS.md

packages/dashboard/app/components/TaskComments.tsx

@@ -1,5 +1,5 @@
 import { useMemo, useState } from "react";
-import type { Task, TaskComment } from "@kb/core";
+import type { Task, TaskComment } from "@fusion/core";
 import { addTaskComment, updateTaskComment, deleteTaskComment } from "../api";
 import type { ToastType } from "../hooks/useToast";