[xmetropolicex]

What does this change?

Adds complete Turkish (tr, shown as “Türkçe”) translations for all 1,019 current UI strings, including the Windows installer. The app selects Turkish automatically for tr and tr-* OS cultures; unrelated codes such as tru keep falling back to English.

Registers the language in the shared app/installer picker, documents /LANG=tr, and adds locale, resource/placeholder, installer and nine-page rendering coverage.

Type of change

• Translation

How was it tested?

• dotnet format Filee.slnx --verify-no-changes --no-restore
• Localization tests: 84 passed
• Installer suite: 155 passed
• Main-window page render tests: 96 passed, including all nine Turkish pages; Turkish screenshots visually checked
• Windows 11: built and installed a self-contained Turkish package based on v2.0.0; checked the Turkish installer and running UI. PNG → JPG, PNG → PDF and JSON containing Turkish characters → YAML conversions succeeded.
• Full dotnet test Filee.slnx -c Release is not green in this Windows environment. The unchanged engine suite reports 1,679 passed, 70 skipped and 10 failed: eight OFD tests pass when rerun with -- xUnit.Culture=en-US; PandocMarkupTests.More_markup_languages_and_slides expects a different route with the installed engines; MediaTests.Progress_rises_while_ffmpeg_works fails its intermediate-progress assertion. No engine or engine-test code is changed here. Core, CLI, Platform and Setup suites pass. The extended App suite was stopped before completion; the separate 84-case localization and 96-case page-render runs above completed successfully.

Screenshots

Generated from the current main-based Turkish sources. Preview images live on a separate branch of the fork, so this PR contains only the seven language/test files.

Checklist

• The new language has every English key and matching numeric placeholders; no new UI keys were introduced.
• No new third-party code or binaries.
• The PR does one thing: Turkish language support.

[KnifeLemon]

Teşekkürler @xmetropolicex! This is a complete and careful translation, and the screenshots and the installer check help a lot.

Main gained six strings after you opened this (the FITS astrophoto options from #505), so I added Turkish for them and merged main into your branch. Have a look at presets.fits_* in tr.json and correct anything that reads wrong. This goes into the next release, together with Turkish on filee.sh.