Multilang: language policy (#25414)

* add draft translation merging policy

* Update policy copy

* copy

* add link

* Update selfdrive/ui/translations/README.md

selfdrive/ui/translations/README.md

@@ -11,6 +11,14 @@
 
 Before getting started, make sure you have set up the openpilot Ubuntu development environment by reading the [tools README.md](/tools/README.md).
 
+### Policy
+
+Most of the languages supported by openpilot come from and are maintained by the community via pull requests. A pull request likely to be merged is one that [fixes a translation or adds missing translations.](https://github.com/commaai/openpilot/blob/lang-policy/selfdrive/ui/translations/README.md#improving-an-existing-language)
+
+We also generally merge pull requests adding support for a new language if there are community members willing to maintain it. Maintaining a language is ensuring quality and completion of translations before each openpilot release.
+
+comma may remove or hide language support from releases depending on translation quality and completeness.
+
 ### Adding a New Language
 
 openpilot provides a few tools to help contributors manage their translations and to ensure quality. To get started:
@@ -39,7 +47,7 @@ Any time you edit source code in the UI, you need to update the translations to
 
 ### Testing
 
-openpilot has a few unit tests to make sure all translations are up to date and that all strings are wrapped in a translation marker. They are run in CI, but you can also run them locally.
+openpilot has a few unit tests to make sure all translations are up-to-date and that all strings are wrapped in a translation marker. They are run in CI, but you can also run them locally.
 
 Tests translation files up to date: