Second failure from the Server 2019 test. The previous fix worked - msiexec went
from exit 1639 (ERROR_INVALID_COMMAND_LINE, which is why it printed its usage
dialog) to exit 1603 (ERROR_INSTALL_FAILURE), so the command line parses now and
the MSI itself is failing.
It failed in 1.1 seconds. An MSI that dies that fast has not begun installing;
it has failed a launch condition. MySQL 8.4 requires the Visual C++
redistributable and a bare Windows Server does not ship it - the same runtime
mysql.exe and mysqldump.exe import, which was visible when their DLL
dependencies were trimmed and went unnoticed.
Stage 0 now installs VC_redist.x64.exe from the bundle before touching MySQL,
skipping it when vcruntime140.dll is already present, and fails with a sentence
naming the requirement if the redistributable is absent from the bundle
altogether. vcredist\ is an optional locked payload.
msiexec also gets /l*v now. A bare 1603 names neither the failing action nor the
reason, and it is the most common MySQL install failure - diagnosing this one
took a launch-condition inference rather than a log. The MSI log lands beside
the installer's own in ProgramData, so the next failure is readable instead of
guessed at.