Rename locale.MustGetAll to GetAll and return error also

Since app.New returns error too, there is no need for locale.GetAll to
panic on error; main will log and close the application.

pkg/app/app.go

@@ -29,7 +29,10 @@ type App struct {
 }
 
 func New(db *database.DB, avatarsDir string) (http.Handler, error) {
-	locales := locale.MustGetAll(context.Background(), db)
+	locales, err := locale.GetAll(context.Background(), db)
+	if err != nil {
+		return nil, err
+	}
 	static := http.FileServer(http.Dir("web/static"))
 	profile, err := newProfileHandler(static, avatarsDir)
 	if err != nil {

pkg/locale/locale.go

@@ -31,15 +31,18 @@ func (m Locales) Tags() []language.Tag {
 	return keys
 }
 
-func MustGetAll(ctx context.Context, db *database.DB) Locales {
-	availableLanguages := mustGetAvailableLanguages(ctx, db)
+func GetAll(ctx context.Context, db *database.DB) (Locales, error) {
+	availableLanguages, err := getAvailableLanguages(ctx, db)
+	if err != nil {
+		return nil, err
+	}
 	locales := map[language.Tag]*Locale{}
 	for _, lang := range availableLanguages {
 		locale := newLocale(lang)
 		locale.AddDomain("camper")
 		locales[lang.tag] = locale
 	}
-	return locales
+	return locales, nil
 }
 
 func newLocale(lang availableLanguage) *Locale {
@@ -85,10 +88,10 @@ type availableLanguage struct {
 	currencyPattern string
 }
 
-func mustGetAvailableLanguages(ctx context.Context, db *database.DB) []availableLanguage {
+func getAvailableLanguages(ctx context.Context, db *database.DB) ([]availableLanguage, error) {
 	rows, err := db.Query(ctx, "select lang_tag, currency_pattern from language where selectable")
 	if err != nil {
-		panic(err)
+		return nil, err
 	}
 	defer rows.Close()
 
@@ -98,13 +101,13 @@ func mustGetAvailableLanguages(ctx context.Context, db *database.DB) []available
 		var currencyPattern string
 		err = rows.Scan(&langTag, &currencyPattern)
 		if err != nil {
-			panic(err)
+			return nil, err
 		}
 		languages = append(languages, availableLanguage{language.MustParse(langTag), currencyPattern})
 	}
 	if rows.Err() != nil {
-		panic(rows.Err())
+		return nil, rows.Err()
 	}
 
-	return languages
+	return languages, nil
 }