Update changelogs from fern repo

fern/products/sdks/overview/typescript/changelog/2025-12-19.mdx

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+## 3.43.0
+**`(feat):`** Add support for endpoint-level security configuration via new `endpoint-security` auth requirement type.
+This allows APIs to specify different authentication schemes per endpoint, enabling fine-grained control
+over which endpoints accept which auth methods (e.g., some endpoints use Bearer, others use API Key).
+
+
+**`(feat):`** Add `RoutingAuthProvider` that dynamically routes authentication requests based on endpoint metadata.
+When `auth: endpoint-security` is configured, the SDK uses endpoint metadata to determine which auth
+provider to use for each request. `AnyAuthProvider` remains the default for `auth: any` configurations.
+
+
+**`(chore):`** Refactor all auth providers to use factory pattern with static `createInstance` methods. This enables
+type-safe provider instantiation, conditional provider creation based on available credentials, and
+better error messages with scheme-specific context.
+
+
+**`(feat):`** Add conditional wrapper properties for auth options to prevent naming conflicts when multiple auth
+schemes are configured (e.g., `options.bearer.token` vs `options.oauth.token`).
+
+
+**`(chore):`** Make `endpointMetadata` parameter optional in `EndpointSupplier.get()` to allow auth providers
+to handle endpoints without metadata gracefully while maintaining backward compatibility.
+
+