* docs(mavlink): add security hardening guide for production deployments
Add a dedicated security hardening page covering MAVLink authentication
risks, a hardening checklist (enable signing, secure physical access,
secure network links), and integrator responsibility for deployment
security. Add a warning block to the main MAVLink page linking to the
new guide.
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Signed-off-by: Ramon Roche <mrpollo@gmail.com>
PX4BuildBot