feat: multiprocess launch for core tests ~x4.64 faster

[dimmarvel]

~4.64× faster, or ~78.5% reduction

Before: Total time: 10078s. (22247ms per test in average)
With multiprocess: Total time: 2165 s. (4790 ms per test in average)

Run example

# Default run with 8 process
./coretests --multiprocess-run 8 

Example of output:

REPORT (aggregated):
  Workers:          8
  Worker failures:  3
  Unique tests run: 452
  Total tests run:  452
  Failures:         3 (postponed failures: 0)
  Postponed:        12
  Total time:       2165 s. (4790 ms per test in average)
FAILED/POSTPONED TESTS:
  FAILED:    hard_fork_6_intrinsic_payment_id_rpc_test
  FAILED:    wallet_true_rpc_pos_mining @ HF 5
  FAILED:    zarcanum_pos_block_math


FAILURE REASONS (workers):
    report: C:\git_repos\zano\build_msvc2022_64\tests\Release\chaingen_runs\w0\coretests_report.json
    logs dir: C:\git_repos\zano\build_msvc2022_64\tests\Release\chaingen_runs\w0
    log file: C:\git_repos\zano\build_msvc2022_64\tests\Release\chaingen_runs\w0\worker.log
    failed tests:
      - hard_fork_6_intrinsic_payment_id_rpc_test
    report: C:\git_repos\zano\build_msvc2022_64\tests\Release\chaingen_runs\w3\coretests_report.json
    logs dir: C:\git_repos\zano\build_msvc2022_64\tests\Release\chaingen_runs\w3
    log file: C:\git_repos\zano\build_msvc2022_64\tests\Release\chaingen_runs\w3\worker.log
    failed tests:
      - zarcanum_pos_block_math
    report: C:\git_repos\zano\build_msvc2022_64\tests\Release\chaingen_runs\w4\coretests_report.json
    logs dir: C:\git_repos\zano\build_msvc2022_64\tests\Release\chaingen_runs\w4
    log file: C:\git_repos\zano\build_msvc2022_64\tests\Release\chaingen_runs\w4\worker.log
    failed tests:
      - wallet_true_rpc_pos_mining @ HF 5

Example of coretests_report.json for worker 0:

{
    "worker_id": "0",
    "processes": "1",
    "tests_count": "27",
    "unique_tests_count": "27",
    "total_time_ms": "2152828",
    "skip_all_till_the_end": "false",
    "exit_code": "1",
    "failed_tests": [
        "hard_fork_6_intrinsic_payment_id_rpc_test"
    ],
    "tests_running_time": [
        {
            "name": "pos_minting_tx_packing",
            "ms": "12469"
        },
        {
            "name": "multisig_unconfirmed_transfer_and_multiple_scan_pool_calls",
            "ms": "6937"
        },
        {
            "name": "escrow_w_and_fake_outputs",
            "ms": "38203"
        },
//...
        {
            "name": "asset_operations_and_chain_switching @ HF 4",
            "ms": "40265"
        },
        {
            "name": "wallet_reorganize_and_trim_test @ HF 6",
            "ms": "28938"
        }
    ]
}

Example of worker 4 worker.log

//...
15# BaseThreadInitThunk in KERNEL32
16# RtlUserThreadStart in ntdll

 Message:

blocks_fetched != top_height because 0 != 13
2026-Jan-23 17:53:36.226787 Mining has been stopped, 0 finished
2026-Jan-23 17:53:36.252388 Storing market...
2026-Jan-23 17:53:36.252388 Market stored OK
2026-Jan-23 17:53:36.252388 Mining has been stopped, 0 finished
2026-Jan-23 17:53:36.253388 ========================================================================
#TEST# >>>> wallet_true_rpc_pos_mining @ HF 5 <<<< FAILED
====================================================================================================
//...