* refactor(pi-ai): replace model-ID pattern matching with capability metadata
Add ModelCapabilities to Model<TApi> and a CAPABILITY_PATCHES mechanism
so call sites read model.capabilities fields instead of parsing model IDs
or hardcoding provider names.
- types.ts: add ModelCapabilities interface (supportsXhigh, requiresToolCallId,
supportsServiceTier, charsPerToken) and capabilities?: ModelCapabilities to
Model<TApi>
- models.ts: add CAPABILITY_PATCHES table applied at registry init; patches
declare GPT-5.x and Opus 4.6 capabilities once instead of repeating ID
checks at every call site; supportsXhigh() now reads capabilities only
- service-tier.ts: extract SERVICE_TIER_MODEL_PREFIXES constant so the gating
list has a single named home; add path comment pointing to issue #2546 for
the full capability-driven follow-up
No behaviour change. New models and providers can declare capabilities in
their model definitions without touching function logic.
Closes#2546
* fix(pi-ai): apply capability patches to custom/discovered/extension models
Models constructed outside the static pi-ai registry (custom models
from models.json, extension-registered models, discovered models)
bypassed CAPABILITY_PATCHES — causing supportsXhigh() to silently
return false for GPT-5.x or Opus 4.6 variants registered through
those paths.
Export applyCapabilityPatches() from pi-ai and call it in ModelRegistry
after model assembly in all three construction paths: loadModels(),
applyProviderConfig(), and discoverModels().
Add regression tests covering patching, precedence, idempotency,
and synthetic models that mimic the custom/extension path.
Closes#2546
f8814f5a15