fix(api): fix import paths missed by router reorganisation

- allocation-conflict-procedures: allocation-shared.js → allocation/shared.js
- allocation/index.ts: add missing allocationConflictProcedures spread
- allocation-conflict-check.test.ts: router/allocation.js → allocation/index.js

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/api/src/__tests__/allocation-conflict-check.test.ts

@@ -1,6 +1,6 @@
 import { AllocationStatus, SystemRole } from "@capakraken/shared";
 import { beforeEach, describe, expect, it, vi } from "vitest";
-import { allocationRouter } from "../router/allocation.js";
+import { allocationRouter } from "../router/allocation/index.js";
 import { createCallerFactory } from "../trpc.js";
 
 vi.mock("../sse/event-bus.js", () => ({