Add Turkish (tr) locale to ember-i18n

[niklasmarderx]

What

Add Turkish translation file to crates/ember-i18n/locales/tr.json.

Why

Ember already supports 11 languages but is missing Turkish, which has a large developer community. Adding locale files is a great way to get started with the codebase.

How

1. Copy crates/ember-i18n/locales/en.json as a template
2. Create crates/ember-i18n/locales/tr.json
3. Translate all strings to Turkish
4. Run cargo test -p ember-i18n to make sure it compiles
5. Add Locale::Turkish variant if not already present in crates/ember-i18n/src/lib.rs

Reference

Look at de.json or es.json for examples of how other translations are structured.