test(mothership): clear handler registry between executor tests

Add clearHandlers() helper and reset the module-level handler registry in
beforeEach so handlers registered in one test do not leak into the next.

Author: TheodoreSpeaks

apps/sim/lib/copilot/tool-executor/executor.test.ts

@@ -25,11 +25,12 @@ vi.mock('@/tools', () => ({
   executeTool: executeAppTool,
 }))
 
-import { executeTool, registerHandler } from './executor'
+import { clearHandlers, executeTool, registerHandler } from './executor'
 
 describe('copilot tool executor fallback', () => {
   beforeEach(() => {
     vi.clearAllMocks()
+    clearHandlers()
   })
 
   it('falls back to app tool executor for dynamic sim tools', async () => {

apps/sim/lib/copilot/tool-executor/executor.ts

@@ -35,6 +35,10 @@ export function hasHandler(toolId: string): boolean {
   return handlerRegistry.has(toolId)
 }
 
+export function clearHandlers(): void {
+  handlerRegistry.clear()
+}
+
 export async function executeTool(
   toolId: string,
   params: Record<string, unknown>,