- byProvider now resolves the internal provider id to its configured
display name via getProviderById() (fallback: raw id for providers
not in the static registry). Fixes the Usage page showing "codex"
instead of "OpenAI Codex".
- byModel's in-memory dedup key now uses the normalized model name
instead of the raw one, so the same logical model recorded under a
bare and a provider-prefixed spelling (e.g. "glm-5.2" vs
"z-ai/glm-5.2") merges into a single aggregated row instead of
appearing twice with the same displayed name.
- Introduces a local UsageRows type alias in route.ts to shrink the
repeated "as Array<Record<string, unknown>>" casts back under the
frozen file-size baseline once the file was touched.
