feat: add multilingual glossary support (backend + frontend types)

Backend:
- Add source_language column to glossaries table
- Add translations JSON column to glossary_terms table
- Alembic migration for schema changes
- format_glossary_for_prompt now language-aware: extracts correct
  translation per target language, falls back to EN reference for
  templates with only FR→EN data
- CRUD routes accept/return source_language and translations
- Pydantic schemas updated

Frontend:
- Types updated: GlossaryTerm now has translations: Record<string, string>
- Glossary/GlossaryListItem now have source_language
- Added SUPPORTED_LANGUAGES constant (13 languages)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

frontend/src/app/dashboard/glossaries/EditGlossaryDialog.tsx

@@ -71,6 +71,7 @@ export function EditGlossaryDialog({
         id: `temp-${i}`,
         source: t.source,
         target: t.target,
+        translations: t.translations || {},
         created_at: null,
       })),
     };

frontend/src/app/dashboard/glossaries/types.ts

@@ -2,12 +2,14 @@ export interface GlossaryTerm {
   id: string;
   source: string;
   target: string;
+  translations: Record<string, string>;
   created_at: string | null;
 }
 
 export interface Glossary {
   id: string;
   name: string;
+  source_language: string;
   terms: GlossaryTerm[];
   created_at: string;
   updated_at: string;
@@ -16,6 +18,7 @@ export interface Glossary {
 export interface GlossaryListItem {
   id: string;
   name: string;
+  source_language: string;
   terms_count: number;
   created_at: string;
 }
@@ -48,6 +51,7 @@ export interface GlossaryUpdateResponse {
 export interface GlossaryTermInput {
   source: string;
   target: string;
+  translations?: Record<string, string>;
 }
 
 export interface GlossaryTermInputWithId extends GlossaryTermInput {
@@ -56,16 +60,34 @@ export interface GlossaryTermInputWithId extends GlossaryTermInput {
 
 export interface GlossaryCreateInput {
   name: string;
+  source_language?: string;
   terms?: GlossaryTermInput[];
 }
 
 export interface GlossaryUpdateInput {
   name?: string;
+  source_language?: string;
   terms?: GlossaryTermInput[];
 }
 
 export const MAX_TERMS_PER_GLOSSARY = 500;
 
+export const SUPPORTED_LANGUAGES: { code: string; label: string; flag: string }[] = [
+  { code: 'en', label: 'English', flag: '🇬🇧' },
+  { code: 'fr', label: 'Français', flag: '🇫🇷' },
+  { code: 'es', label: 'Español', flag: '🇪🇸' },
+  { code: 'de', label: 'Deutsch', flag: '🇩🇪' },
+  { code: 'pt', label: 'Português', flag: '🇧🇷' },
+  { code: 'it', label: 'Italiano', flag: '🇮🇹' },
+  { code: 'nl', label: 'Nederlands', flag: '🇳🇱' },
+  { code: 'ru', label: 'Русский', flag: '🇷🇺' },
+  { code: 'ja', label: '日本語', flag: '🇯🇵' },
+  { code: 'ko', label: '한국어', flag: '🇰🇷' },
+  { code: 'zh', label: '中文', flag: '🇨🇳' },
+  { code: 'ar', label: 'العربية', flag: '🇸🇦' },
+  { code: 'fa', label: 'فارسی', flag: '🇮🇷' },
+];
+
 // Generate unique IDs for React keys
 let idCounter = 0;
 export function generateTermId(): string {