- install: resolve the image directory from the version's settings type and
skip image handling for docker appliances; guard appliance.images
- appliance schema: validate template_properties against template_type,
align cpu_throttling with the qemu template, add kvm and version idlepc
- conversion: map IOU image to path, kvm disable to accel=tcg, inherit only
same-type default settings, symbol fallback from the effective category,
template_properties cannot override structural fields
- allow clearing netmiko_device_type with an empty string
- download the template symbol regardless of the level it is defined at and
give qemu guests a default symbol
Common template field (schema + templates table column + Alembic
migration) holding the Netmiko device type (e.g. 'cisco_xr', 'nokia_srl')
so Netmiko/Nornir based tooling can look up how to reach a node's CLI
without hard-coded vendor mappings. Free-form lowercase string on
purpose: Netmiko's platform list evolves independently of GNS3.
