Swap the keystore through a temp and .old file on Windows instead
of relying on os.Rename alone, which is not reliably atomic there.
Signed-off-by: Bryan Frimin <bryan@probo.com>
Introduce the standalone device agent binary and shared library
for enrollment, posture checks, self-update, and OS service
integration. Include build targets, module deps, and release
workflow so the agent can ship independently of server changes.
Signed-off-by: Bryan Frimin <bryan@probo.com>