Add regression test for stale cached-null + duplicate-key race condition in GrouperWorker

[Copilot]

The existing CacheController mock always invokes the resolver and treats del as a no-op, making it impossible to reproduce the race condition where a stale null is cached and must be invalidated before a retry. Without a real caching layer in tests, the infinite-recursion bug introduced by a duplicate-key error could silently regress.

Changes

• Regression test using real CacheController — uses jest.requireActual to bypass the global mock, giving the test genuine cache semantics (null is cached; del actually evicts)
• Race condition simulation — pre-inserts the event in the DB (Worker B wins the race), then manually poisons the cache key with null (Worker A's stale entry); the unique index on groupHash causes the real insertOne to throw E11000
• Two-pronged assertion — verifies cache.del was called with the exact stale key, and that totalCount increments to 2 (retry found the DB record and processed it as a repetition rather than recursing)

// Real cache so null is actually cached and del actually evicts
const RealCacheController = jest.requireActual('../../../lib/cache/controller').default;
const realCache = new RealCacheController();
(worker as any).cache = realCache;

// Stale null — Worker A cached "not found" before Worker B's insert
realCache.set(eventCacheKey, null);

await worker.handle(task);
// E11000 from DB → cache.del(eventCacheKey) → retry finds real event
expect(delSpy).toHaveBeenCalledWith(eventCacheKey);
expect(savedEvent.totalCount).toBe(2);

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  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node node ./postinstall.js /home/REDACTED/.cache/node-gyp/24.14.0/deps/uv/include -I /home/REDACTED/.cache/node-gyp/24.14.0/deps/zlib .node" "Release/sshcrypto.node" 2>/dev/null || (rm -rf "Release/sshcrypto.node" && cp -af "Release/obj.target/sshcrypto.node" "Release/sshcrypto.node")' > ./Release/.deps/Rele /home/REDACTED/.cache/node-gyp/24.14.0/deps/v8/include -I ../../../../../nan --64 -o Release/obj.target/sshcrypto/src/binding.o conf�� s. pull.rebase /usr/local/bin/bash (dns block)
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node node node_modules/.bin/jest --testPathPattern=workers/grouper/tests/index --testNamePattern=stale null conf�� e/common.gypi user.email tures/node_modules/.bin/as 14.0 /x64/lib/node_mo-c 14.0/<(target_ar# remove blank lines; /hawk.workers/no-I e pu_features/src/-I (dns block)

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