Add Turkish option to navbar language selector

- Updated the navbar to include the Turkish language option.
- Added the Turkish flag SVG to the assets folder.
- Translated a portion of the .properties file to support Turkish.

src/main/resources/templates/fragments/languages.html

@@ -47,6 +47,9 @@
          <a class="dropdown-item lang_dropdown-item" href="" data-bs-language-code="sv_SE">
              <img src="images/flags/se.svg" alt="icon" width="20" height="15"> Svenska
          </a>
+         <a class="dropdown-item lang_dropdown-item" href="" data-language-code="tr_TR">
+            <img src="images/flags/tr.svg" alt="icon" width="20" height="15"> Türkçe
+        </a>
          <a class="dropdown-item lang_dropdown-item" href="" data-bs-language-code="ru_RU">
              <img src="images/flags/ru.svg" alt="icon" width="20" height="15"> Русский
          </a>