test: eliminate AsyncFeatureSpec test-setup family (convert async suites to sync)

[hongwei1]

Background

During the dispatch-core → OkHttp3 migration (#9, PR #28), a family of *ServerSetupAsync test-setup traits and async-style test suites survived in the test tree.

Clarification: the "Async" here is ScalaTest's AsyncFeatureSpec test-writing style (test bodies return Future[Assertion]), not the dispatch/AsyncHttpClient HTTP client (removed in #9) and not the http4s server framework. The async request helpers (makePostRequestAsync etc.) are fake-async — Future { blocking { syncCall } } wrappers. No real concurrent I/O happens in these suites.

Goal

Fully remove the async test-setup style: convert all async-style suites to ordinary synchronous suites, then delete the async setup traits.

Scope

Keep (do NOT touch)

• SendServerRequests async request methods (makeGetRequestAsync / makePostRequestAsync / makePutRequestAsync / makeDeleteRequestAsync / getAPIResponseAsync) — still used by the genuine concurrency tests (code.concurrency.Concurrent*Test, which extend ConcurrentRaceSetup, not ServerSetupAsync).

Convert to sync (9 suites)

• v4_0_0: PasswordRecoverTest, EntitlementTests, BankTests, ConsentTests
• v5_0_0: BankTests, ConsentRequestTest, ATMTest, UserAuthContextTest, CustomerTest

Conversion patterns:

1. Mechanical unwrap — makeXxxRequestAsync → makeXxxRequest, collapse response map { r => … } into direct response.….
2. for-comprehension with real production Futures (v4/v5 BankTests) — Await.result the genuine NewStyle.function.* Futures, sync test requests, inline assertions.
3. Pure trait switch — suites that extend an Async trait but already write sync assertions (lifted by convertAssertionToFutureAssertion): just switch VxxxServerSetupAsync → VxxxServerSetup.

Delete (6 files)

• v3_0_0/WarehouseTestAsync.scala (redundant with existing sync WarehouseTest)
• v3_0_0/V300ServerSetupAsync.scala
• v3_1_0/V310ServerSetupAsync.scala (already dead — zero references)
• v4_0_0/V400ServerSetupAsync.scala
• v5_0_0/V500ServerSetupAsync.scala
• setup/ServerSetupAsync.scala (both ServerSetupAsync + ServerSetupWithTestDataAsync)

Verification

• mvn test-compile zero errors
• Affected v3/v4/v5 suites green
• Concurrency tests still green (async helpers retained)
• Full local run_tests_parallel.sh gate green