release 1.20.0: domains.conf locale l10n + optional German UI

Add locale column (fr-CH for FP, de-CH elsewhere; ch-FR/ch-DE aliases).
Introduce UI lang=de (tags + sticky) without using de as any stock default.

lib.sh

@@ -166,24 +166,53 @@ set_taler_stack() {
   fi
 }
 
-# Normalize domains.conf lang token → en|fr (empty if not a lang token).
+# Normalize domains.conf UI lang token → en|fr|de (empty if not a lang token).
+# Note: de is valid for --lang / explicit profile, but no stock profile defaults to de.
 _domain_lang_token() {
   case "${1:-}" in
     en|EN|eng|english) printf 'en' ;;
     fr|FR|fra|french) printf 'fr' ;;
+    de|DE|deu|ger|german|deutsch) printf 'de' ;;
     *) printf '' ;;
   esac
 }
 
+# Normalize regional locale → BCP 47 (fr-CH, de-CH, en-CH, …). Empty if unknown.
+# Accepts fr-CH, fr_CH, ch-FR / de-CH, ch-DE (user-friendly aliases).
+_domain_locale_token() {
+  local t="${1:-}"
+  t=$(printf '%s' "$t" | tr '[:upper:]' '[:lower:]' | tr '_' '-')
+  case "$t" in
+    fr-ch|ch-fr|fr_ch) printf 'fr-CH' ;;
+    de-ch|ch-de|de_ch) printf 'de-CH' ;;
+    en-ch|ch-en|en_ch) printf 'en-CH' ;;
+    en-us|en-gb|fr-fr|de-de|it-ch|rm-ch)
+      # pass through other xx-YY
+      printf '%s' "$t" | awk -F- '{printf "%s-%s", tolower($1), toupper($2)}'
+      ;;
+    *)
+      # bare xx-YY pattern
+      if printf '%s' "$t" | grep -qE '^[a-z]{2}-[a-z]{2}$'; then
+        printf '%s' "$t" | awk -F- '{printf "%s-%s", tolower($1), toupper($2)}'
+      else
+        printf ''
+      fi
+      ;;
+  esac
+}
+
 # Load first matching profile from domains.conf.
 # Fields (whitespace-separated; # comments; blank lines ignored):
-#   name  bank  exchange  merchant  currency  local[0|1]  landing[0|1]  lang[en|fr]  [canonical]
-# Legacy: 8th field may be canonical only (no lang) — lang defaults to en.
-# Sets TALER_DOMAIN_LANG from the profile (i18n source of truth when SET≠1).
+#   name  bank  exchange  merchant  currency  local  landing  lang  locale  [canonical]
+# Legacy:
+#   … landing  lang  [canonical]           → locale defaulted
+#   … landing  [canonical]                 → lang=en, locale defaulted
+# Sets TALER_DOMAIN_LANG + TALER_DOMAIN_LOCALE from the profile.
 # Returns 0 if found, 1 if not.
 load_domain_profile() {
   local want="$1" conf="${TALER_DOMAINS_CONF:-}"
-  local line name bank exchange merchant currency local_stack landing canon profile_lang f8 f9
+  local line name bank exchange merchant currency local_stack landing canon
+  local profile_lang profile_locale f8 f9 f10
   [ -n "$want" ] || return 1
   [ -n "$conf" ] && [ -f "$conf" ] || return 1
 
@@ -202,28 +231,53 @@ load_domain_profile() {
     landing="${7:-}"
     f8="${8:-}"
     f9="${9:-}"
+    f10="${10:-}"
     canon="$name"
     profile_lang=""
+    profile_locale=""
     # Backward compat: old 7th field was canonical domain (contains a dot)
     if [ -n "$landing" ] && [[ "$landing" == *.* && "$landing" != "0" && "$landing" != "1" ]]; then
       canon="$landing"
       landing=""
       f8="${7:-}"
       f9="${8:-}"
+      f10="${9:-}"
     fi
     if [ -n "$f8" ]; then
       profile_lang=$(_domain_lang_token "$f8")
       if [ -n "$profile_lang" ]; then
-        canon="${f9:-$name}"
+        # modern: lang [locale] [canonical]
+        profile_locale=$(_domain_locale_token "$f9")
+        if [ -n "$profile_locale" ]; then
+          canon="${f10:-$name}"
+        else
+          # lang + canonical (no locale column)
+          if [ -n "$f9" ] && [ -z "$(_domain_lang_token "$f9")" ]; then
+            canon="$f9"
+          else
+            canon="${f9:-$name}"
+          fi
+          profile_locale=$(_domain_locale_token "$f10")
+        fi
       else
-        # legacy: field 8 = canonical, optional field 9 = lang
+        # legacy: field 8 = canonical only
         canon="$f8"
         profile_lang=$(_domain_lang_token "$f9")
+        profile_locale=$(_domain_locale_token "${f10:-$f9}")
+        [ -z "$profile_lang" ] && profile_lang=en
       fi
     fi
     [ -z "$profile_lang" ] && profile_lang=en
+    if [ -z "$profile_locale" ]; then
+      # default regional locale: FP → fr-CH, else de-CH
+      case "$name$canon$bank$merchant" in
+        *lefrancpaysan*|*francpaysan*) profile_locale=fr-CH ;;
+        *) profile_locale=de-CH ;;
+      esac
+    fi
     TALER_DOMAIN_LANG="$profile_lang"
-    export TALER_DOMAIN_LANG
+    TALER_DOMAIN_LOCALE="$profile_locale"
+    export TALER_DOMAIN_LANG TALER_DOMAIN_LOCALE
     set_taler_stack "$bank" "$exchange" "$merchant" "$currency" "$local_stack" "$landing" "$canon"
     return 0
   done <"$conf"