Add per-resource cursors, fetch-by-id, and full backfill to WHOOP sync

Replace the single shared last-synced cursor with a per-resource cursor map
on the WHOOP connection. Recovery, sleep, workout, and cycle each advance only
their own cursor on a successful fetch+upsert, so a slow or 403-ing collection
never drags the incremental window forward for its siblings and its own
late-arriving records stay inside the overlap. Legacy connections fall back to
the shared last-synced instant, so no historical state is lost.

Add single-record fetch-by-id client routes and per-resource by-id syncs. The
update webhook now carries the resource id through the queue payload, so the
worker resolves and upserts that one record immediately rather than re-walking
the whole collection on the next overlap tick.

Anchor a full sync at a fixed deep-history point instead of returning no lower
bound, so a backfill covers the multi-year span an incremental tick would skip
and a stale cursor cannot silently narrow it.

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",
     });
   });