fix(FN-3165): remove remaining core roadmap type exports

- Remove the legacy roadmap type re-exports from @fusion/core types
- Update core index exports to stop exposing roadmap plugin types
- Switch dashboard roadmap route test type import to the roadmap plugin package

Fusion-Task-Id: FN-3165

packages/dashboard/src/__tests__/roadmap-routes.routes.test.ts

@@ -5,7 +5,7 @@ import express from "express";
 import { get as performGet, request as performRequest } from "../test-request.js";
 import { createRoadmapRouter } from "../roadmap-routes.js";
 import { ApiError } from "../api-error.js";
-import type { Roadmap, RoadmapMilestone, RoadmapFeature, RoadmapStore } from "@fusion/core";
+import type { Roadmap, RoadmapMilestone, RoadmapFeature, RoadmapStore } from "@fusion-plugin-examples/roadmap";
 
 
 // vi.mock is hoisted