chore: add changeset for ui_locales feature (#7825)

Author: charIeszhao

.changeset/great-starfishes-help.md

@@ -0,0 +1,31 @@
+---
+"@logto/core": minor
+"@logto/experience": minor
+"@logto/schemas": minor
+"@logto/connector-kit": minor
+---
+
+add support to the OIDC standard authentication parameter `ui_locales`
+
+We are now supporting the standard OIDC `ui_locales` auth parameter to customize the language of the authentication pages. You can pass the `ui_locales` parameter in the `signIn` method via the `extraParams` option in all Logto SDKs.
+
+### What it does
+
+- Determines the UI language of the Logto-hosted sign-in experience at runtime. Logto picks the first language tag in `ui_locales` that is supported in your tenant's language library.
+- Affects email localization for messages triggered by the interaction (e.g., verification code emails).
+- Exposes the original value to email templates as a variable `uiLocales`, allowing you to include it in the email subject/content if needed.
+
+### Example
+
+If you want to display the sign-in page in French (Canada), you can do it like this:
+
+```ts
+await logtoClient.signIn({
+  redirectUri: 'https://your.app/callback',
+  extraParams: {
+    ui_locales: 'fr-CA fr en',
+  },
+});
+```
+
+Refer to the [documentation](https://docs.logto.io/end-user-flows/authentication-parameters/ui-locales) for more details.