Preserve class-based API configuration in React options

[sylvesterkaczmarek]

Problem

The React options wrapper recursively copies every object into a plain object, although its equality check already treats non-plain objects by identity. A structurally valid class-based HostedApiConfig consequently loses its prototype getClientSecret method and private state before it reaches the component.

Change

Traverse only plain objects and arrays when creating the latest-function wrappers. Retain other object instances by reference, consistent with the existing comparison policy. Nested functions in plain option objects continue to resolve through the latest options. Add a patch changeset; no dependencies or public types change.

Validation

• 25 tests passed, including nine new cases. Eight of those fail on unchanged production code; the null-prototype plain-object control passes before and after.
• The primary reproductions use a class that implements the actual HostedApiConfig interface, with a prototype method and a private field. Tests also cover replacement-instance comparison, surrounding callback updates, and non-plain leaf identity.
• CI=1 pnpm check passed formatting, lint, type checks, documentation generation, and tests.
• React ESM, CommonJS, and declaration builds passed. git diff --check passes.

Node 26.8.1 and Vitest 3.2.4 on macOS arm64. Tests exercise the production option-shaping helper with synthetic configurations. No live authentication, hosted ChatKit, or browser session was used. This does not expand the public options schema or change listener timing.

Reproduced against 22613848a656077a408788f028c7727e38d10449.