feat(ai-sdk): export GoogleCacheRegistry + eval fixtures helpers (#46)

.changeset/ai-sdk-export-cache-registry-eval-helpers.md

@@ -0,0 +1,7 @@
+---
+"@gemstack/ai-sdk": minor
+---
+
+Export `GoogleCacheRegistry` (+ `GoogleCacheRegistryOptions` / `CacheStoreLike`) from the main entry, and `defaultFixturesDir` / `readFixture` / `writeFixture` from the `./eval` subpath.
+
+These were gemstack-internal symbols that framework bindings could not reach against a published build. Surfacing them lets a binding construct the Gemini context-cache registry with its own `CacheAdapter` (`new GoogleCacheRegistry({ store })`) and lets an `ai:eval` CLI binding read/write recorded fixtures. Purely additive; unblocks relocating the `/server` provider and the `ai-eval` command to the Rudder side.

packages/ai-sdk/src/eval/index.ts

@@ -42,7 +42,7 @@ import { z } from 'zod'
 
 export { reportJson } from './json-reporter.js'
 export type { SuiteJson, SuiteJsonCase } from './json-reporter.js'
-export { stepsFromResponse } from './fixtures.js'
+export { stepsFromResponse, defaultFixturesDir, readFixture, writeFixture } from './fixtures.js'
 export type { EvalFixture } from './fixtures.js'
 export { reportHtml } from './html-reporter.js'
 export type { HtmlReportOptions } from './html-reporter.js'

packages/ai-sdk/src/index.ts

@@ -81,6 +81,12 @@ export { AiRegistry } from './registry.js'
 export { AnthropicProvider, type AnthropicConfig } from './providers/anthropic.js'
 export { OpenAIProvider, OpenAIAdapter, type OpenAIConfig } from './providers/openai.js'
 export { GoogleProvider, type GoogleConfig } from './providers/google.js'
+// Google context-cache registry — the runtime class that backs Gemini's
+// `cachedContent` resources. Exported so framework bindings can construct
+// it with their own `CacheAdapter` (`new GoogleCacheRegistry({ store })`)
+// and wire it into the Google provider.
+export { GoogleCacheRegistry } from './providers/google-cache-registry.js'
+export type { GoogleCacheRegistryOptions, CacheStoreLike } from './providers/google-cache-registry.js'
 export { OllamaProvider, type OllamaConfig } from './providers/ollama.js'
 export { DeepSeekProvider, type DeepSeekConfig } from './providers/deepseek.js'
 export { XaiProvider, type XaiConfig } from './providers/xai.js'