fix: restore repo typecheck after provider request settings change

The required Provider.Request settings field and tsgo's literal
narrowing broke typecheck in llm and core; CI missed it because turbo
replayed cached typecheck results for packages whose own sources did
not change.

- anthropic-messages: lower adaptive thinking display with explicit
  literal branches so tsgo keeps the union type
- runner model: annotate providerOptions with its index-signature
  return type
- tests: construct provider requests with the now-required settings
  field and copy them mutably for plugin drafts

packages/core/test/plugin/provider-opencode.test.ts

@@ -373,7 +373,7 @@ describe("OpencodePlugin", () => {
             cost: cost(1),
           })
           catalog.provider.update(provider.id, (draft) => {
-            draft.request = provider.request
+            draft.request = { settings: {}, headers: {}, body: { apiKey: "configured" } }
           })
           catalog.model.update(provider.id, model.id, (draft) => {
             draft.cost = [...model.cost]