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/router/allocation-conflict-procedures.ts

@@ -6,7 +6,7 @@ import {
 import { TRPCError } from "@trpc/server";
 import { z } from "zod";
 import { managerProcedure } from "../trpc.js";
-import { toIsoDate } from "./allocation-shared.js";
+import { toIsoDate } from "./allocation/shared.js";
 
 const CheckConflictsInputSchema = z.object({
   resourceId: z.string(),