cortexkit-provider-usage 0.2.0: add optional apiProvider field

[ualtinok]

Adds ProviderUsage.api_provider (wire apiProvider, camelCase, omitted when absent) — the canonical models.dev provider slug alongside the CodexBar provider name.

Why: three consumers (ALF's router reads, the ck CLI renderer, astrocyte's capacity axis) each hand-roll the same CodexBar-name→canonical translation (claude→anthropic, codex→openai, gemini→google, grok→xai). This field gives them one canonical name to key on, killing the per-consumer maps and their drift risk. astrocyte's capacity↔spend join specifically needs the canonical name to match broca's model-catalog-keyed spend facts.

Contract: populated when the producer knows the canonical name; absent for providers with no models.dev counterpart (antigravity, cursor, factory, etc.), where consumers fall back to provider.

Compatibility: additive + skip-if-none — entries without it serialize byte-identically to 0.1.0. Version bumped 0.1.0→0.2.0 (struct gains a field). The quota module populates it centrally in its read path; ALF/ck consume it when present. Publish is tag-driven per release.yml (cortexkit-provider-usage-v0.2.0) once merged.

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Summary by cubic

Add optional apiProvider to ProviderUsage to expose the canonical models.dev provider slug alongside provider.

• New Features
  • Added optional apiProvider to ProviderUsage (serialized as camelCase, omitted when not set).
  • Carries the canonical models.dev slug (e.g., codex→openai, claude→anthropic); producers set when known, consumers fall back to provider otherwise.
  • Removes per-consumer provider maps in ALF router, ck CLI, and astrocyte capacity axis.
  • Bumped cortexkit-provider-usage to 0.2.0; change is additive and backward compatible.

^{Written for commit 2f1d4cd. Summary will update on new commits.}