[okatu-loli]

v3.65.0 is missing all 22 FreeBSD and musl archives even though the release jobs succeeded. FreeBSD still used the expired active-release sysroot URL, musl downloads timed out at musl.cc, and build.sh continued after compilation failures and uploaded only checksum files.

• Reuse the SHA-256-verified archived FreeBSD sysroot builder for stable releases, preserving the i386 asset name and passing stable version metadata and jsoniter tags.
• Move development and stable musl builds to the existing GitHub toolchain archive, pinned to 2025.06.05; use the same version for Docker and invalidate its old cache. All 21 distinct toolchains referenced by build.sh are present in this release.
• Stop build.sh on command/pipeline failure, fail HTTP downloads with bounded connection waits and retries, allow an absent beta tag, and skip release metadata fetching for prepare/zip.
• Generate release MD5 manifests from archives only, excluding the manifest itself; assert the complete checksum entry set in regression tests.
• Reject empty packaging output and require matching uploaded artifacts in stable, beta, regular-build and Docker workflows.
• Add PR CI regression tests for download/compiler failures, corrupt FreeBSD sysroots, empty packaging, web setup failures and the existing 3/8/11 FreeBSD/musl/musl ARM archive counts.

Validation: six local regression tests passed using simulated downloads/compilers; bash syntax, ShellCheck error-level checks, actionlint and git diff --check passed. The fixed archive was checked live for every referenced toolchain. PR CI passed all 16 checks at 5bb1b5f. A separate recovery build compiled and validated all 22 missing packages from the original v3.65.0 source with the SHA-256-pinned 3.65.0 frontend; it also ran the amd64 musl binary and confirmed the original release version and commit. This PR does not republish or modify v3.65.0 assets; rerunning the old tag alone would still execute its old scripts.