feat(whoop): per-resource cursors, by-id refresh, and full-sync backfill

Give each WHOOP collection its own incremental cursor in a resource_cursors
map so a slow or rejecting collection no longer drags the sync window forward
for its siblings; legacy connections fall back to the shared last-synced
timestamp. The update webhook now carries the record id and triggers a
targeted single-record refresh instead of re-walking the collection, and a
full sync anchors at a fixed deep start so a backfill covers the span an
incremental tick skips. Cursor advances are a single atomic update guarded by
GREATEST so the independent resource queues cannot race each other backward.

Ingest row shape, source tagging, and upsert keys are unchanged.

src/app/api/whoop/webhook/[token]/__tests__/route.test.ts

@@ -162,8 +162,11 @@ describe("POST /api/whoop/webhook/[token]", () => {
       where: { whoopUserId: "42" },
       select: { userId: true },
     });
+    // v1.16.16 (iOS #17) — the resource id rides through so the worker can do
+    // a targeted fetch-by-id refresh instead of re-walking the collection.
     expect(send).toHaveBeenCalledWith("whoop-recovery-sync", {
       userId: "user-1",
+      resourceId: "abc",
     });
   });