fix: streamline locale handling and UI documentation per PR feedback (B…

…larc#309)

- Simplify locale display format in prompts to use English language names
- Remove redundant Elvis operator in locale retrieval
- Replace deprecated Locale constructor with forLanguageTag()
- Add collator comments explaining locale-aware sorting rationale
- Include contextual help about language display differences

src/main/kotlin/com/github/blarc/ai/commits/intellij/plugin/AICommitsUtils.kt

@@ -41,8 +41,7 @@ object AICommitsUtils {
     fun constructPrompt(promptContent: String, diff: String, branch: String, hint: String?, project: Project): String {
         var content = promptContent
         val locale = project.service<ProjectSettings>().locale
-        // lang format: "Language name in English + (ISO 639 lang code) + – + native language name in IDE's locale"; example "French (fr) – français"
-        content = content.replace("{locale}", "${locale.getDisplayLanguage(Locale.ENGLISH)} (${locale.language}) \u2013 ${locale.getDisplayLanguage(locale)}")
+        content = content.replace("{locale}", locale.getDisplayLanguage(Locale.ENGLISH))
         content = content.replace("{branch}", branch)
         content = replaceHint(content, hint)
 
@@ -178,6 +177,6 @@ object AICommitsUtils {
     }
 
     fun getIDELocale(): Locale {
-        return DynamicBundle.getLocale() ?: Locale.getDefault()
+        return DynamicBundle.getLocale()
     }
 }

src/main/kotlin/com/github/blarc/ai/commits/intellij/plugin/settings/AICommitsListCellRenderer.kt

@@ -21,7 +21,7 @@ class AICommitsListCellRenderer : DefaultListCellRenderer() {
             is Locale -> {
                 val ideLocale = AICommitsUtils.getIDELocale()
                 // lang format: "Language name in IDE's locale + (ISO 639 lang code)"; example for Spanish in IDE "francés (fr)", for IDE in German "Französisch (fr)"
-                text = "${Locale(value.language).getDisplayName(ideLocale)} (${value.language})"
+                text = "${Locale.forLanguageTag(value.language).getDisplayLanguage(ideLocale)} (${value.language})"
             }
 
             is Prompt -> {

src/main/kotlin/com/github/blarc/ai/commits/intellij/plugin/settings/AppSettingsConfigurable.kt

@@ -82,6 +82,8 @@ class AppSettingsConfigurable(val project: Project, cs: CoroutineScope) : BoundC
             label(message("settings.locale")).widthGroup("labelPrompt")
             val ideLocale = AICommitsUtils.getIDELocale()
 
+            // Configures locale-aware text comparator for proper language name sorting
+            // Without a Collator, we would get incorrect sorting based on raw Unicode values
             val collator = Collator.getInstance(ideLocale).apply {
                 strength = Collator.TERTIARY
                 decomposition = Collator.CANONICAL_DECOMPOSITION
@@ -100,6 +102,8 @@ class AppSettingsConfigurable(val project: Project, cs: CoroutineScope) : BoundC
                 .widthGroup("input")
                 .bindItem(getter = { projectSettings.locale }, setter = { setActiveLocale(it)} )
 
+            contextHelp(message("settings.locale.contextHelp"))
+
             browserLink(message("settings.more-prompts"), AICommitsBundle.URL_PROMPTS_DISCUSSION.toString())
                 .align(AlignX.RIGHT)
         }

src/main/resources/messages/AiCommitsBundle.properties

@@ -3,6 +3,7 @@ name=AI Commits
 settings.title=Settings
 settings.general.group.title=AI Commits
 settings.locale=Locale
+settings.locale.contextHelp=Listed locales appear in the IDE's language. Prompts use English locales (e.g., German, French, etc.).
 settings.prompt=Prompt
 settings.report-bug=Report bug
 settings.verifyToken=Verify