ModelEntry and CortexModelEntry gain a `capabilities: Vec<String>`
field (serde-default for back-compat). The poller copies it verbatim
from each neuron's ModelInfo.capabilities; list_models computes the
union across every node where a model is loaded so a checkpoint loaded
text-only on one neuron and text+vision on another reports both to the
fleet. Catalogue-only and mid-prewarm entries default to empty until
the catalogue gains a capabilities declaration.
Aliases inherit their target's capability union. New gateway test mocks
two nodes with differing capability arrays and asserts the unioned
/v1/models response.
Closes part of #16 (Stage C3).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
rob thijssen
4972c7d1e7
