junixsocket 2.6.1

• Add AFSocket.checkConnectionClosed to probe connection status
• Fix connection status checks and error handling
• Fix bind behavior on Windows, support re-bind with reuseAddress
• Fix and improve unit tests/selftests, remove several false-positive errors found in the wild (Azure Cloudshell/Microsoft CBL-Mariner 2.0, Amazon EC2, OpenBSD, etc.)
• Fix SimpleTestServer demo, actually counting now to 5, not 6.
• Make builds reproducible, align timestamps with git commit

NOTE: If you're seeing unexpected errors in selftest, please verify with the attached junixsocket-selftest-2.6.1-hotpatch-jar-with-dependencies.jar. There may be false-positive socket timeout issues on very slow machines (e.g., qemu s390).