Add German IPA support (wiki-pronunciation-dict + epitran)

Hybrid approach mirroring English IPA:
- Primary: wiki-pronunciation-dict (636k entries, CC-BY-SA, Wiktionary)
- Fallback: epitran rule-based G2P (MIT license)

IPA modes now use language-appropriate dictionaries:
- auto/en: English IPA (Britfone + eng_to_ipa)
- de: German IPA (wiki-pronunciation-dict + epitran)
- all: EN column gets English IPA, other columns get German IPA
- none: disabled

Frontend shows CC-BY-SA attribution when German IPA is active.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

admin-lehrer/components/grid-editor/GridToolbar.tsx

@@ -22,6 +22,7 @@ interface GridToolbarProps {
 const IPA_LABELS: Record<IpaMode, string> = {
   auto: 'IPA: Auto',
   en: 'IPA: nur EN',
+  de: 'IPA: nur DE',
   all: 'IPA: Alle',
   none: 'IPA: Aus',
 }
@@ -93,16 +94,26 @@ export function GridToolbar({
       </button>
 
       {/* IPA mode */}
-      <select
-        value={ipaMode}
-        onChange={(e) => onIpaModeChange(e.target.value as IpaMode)}
-        className="px-2 py-1.5 text-xs rounded-md border border-gray-200 dark:border-gray-700 bg-white dark:bg-gray-800 text-gray-600 dark:text-gray-400"
-        title="Lautschrift (IPA): Auto = nur bei erkannten englischen Woertern, Alle = fuer alle Vokabeln, Aus = keine"
-      >
-        {(Object.keys(IPA_LABELS) as IpaMode[]).map((m) => (
-          <option key={m} value={m}>{IPA_LABELS[m]}</option>
-        ))}
-      </select>
+      <div className="flex items-center gap-1">
+        <select
+          value={ipaMode}
+          onChange={(e) => onIpaModeChange(e.target.value as IpaMode)}
+          className="px-2 py-1.5 text-xs rounded-md border border-gray-200 dark:border-gray-700 bg-white dark:bg-gray-800 text-gray-600 dark:text-gray-400"
+          title="Lautschrift (IPA): Auto = nur erkannte EN-Woerter, DE = deutsches IPA (Wiktionary), Alle = EN + DE, Aus = keine"
+        >
+          {(Object.keys(IPA_LABELS) as IpaMode[]).map((m) => (
+            <option key={m} value={m}>{IPA_LABELS[m]}</option>
+          ))}
+        </select>
+        {(ipaMode === 'de' || ipaMode === 'all') && (
+          <span
+            className="text-[9px] text-gray-400 dark:text-gray-500 cursor-help"
+            title="DE-Lautschrift: Wiktionary (CC-BY-SA 4.0) + epitran (MIT). EN-Lautschrift: Britfone (MIT) + eng_to_ipa (MIT)."
+          >
+            CC-BY-SA
+          </span>
+        )}
+      </div>
 
       {/* Syllable mode */}
       <select

admin-lehrer/components/grid-editor/useGridEditor.ts

@@ -14,7 +14,7 @@ export interface GridEditorState {
   selectedZone: number | null
 }
 
-export type IpaMode = 'auto' | 'all' | 'en' | 'none'
+export type IpaMode = 'auto' | 'all' | 'de' | 'en' | 'none'
 export type SyllableMode = 'auto' | 'all' | 'de' | 'en' | 'none'
 
 export function useGridEditor(sessionId: string | null) {