The merge consolidates mock helpers across packages by creating a new shared `mockCoreEngine.ts` in the CLI package and strengthening the core/engine helpers, then migrating both CLI command tests and the dashboard's `AgentsView` tests to use the canonical helpers. It also publishes SSE architecture
Fusion-Task-Id: FN-3053
This merge introduces canonical mock helper modules across the dashboard and engine packages, and migrates representative test suites to use them for consistency. The changes add four new mock helpers (`mockApi.ts`, `mockLucide.ts`, `mockCore.ts`, `mockCoreEngine.ts`) and harden the API mock proxy's
Fusion-Task-Id: FN-3044
