Add explicit `claude-sonnet-5` and `claude-sonnet-5-thinking` entries to the
web-server PRICING_REGISTRY at the standard Sonnet rates ($3/$15 in/out,
$3.75/$0.30 cache).
The model catalog and dashboard already ship Sonnet 5 (it is the Claude
default), but pricing was missing: getModelPricing() fell through to
UNKNOWN_MODEL_PRICING, which only coincidentally matches Sonnet rates. As a
result hasCustomPricing('claude-sonnet-5') returned false and getKnownModels()
omitted it, so Sonnet 5 was treated as an unknown model in cost accounting and
known-model listings.
Registering it explicitly makes the pricing intentional and consistent with
every other Claude model, without changing any resolved values.
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Sergey Galuza
1e63c37baf