feat(glossaries): add target_language support - DB migration, API, and UI language pair display

routes/glossary_routes.py

@@ -57,6 +57,7 @@ def _format_glossary(glossary: Glossary) -> dict:
         "id": glossary.id,
         "name": glossary.name,
         "source_language": glossary.source_language,
+        "target_language": getattr(glossary, "target_language", "en") or "en",
         "terms": [_format_term(t) for t in glossary.terms] if glossary.terms else [],
         "created_at": glossary.created_at.isoformat() if glossary.created_at else None,
         "updated_at": glossary.updated_at.isoformat() if glossary.updated_at else None,
@@ -106,6 +107,7 @@ async def create_glossary(
                 user_id=user.id,
                 name=body.name,
                 source_language=body.source_language,
+                target_language=body.target_language,
                 created_at=datetime.now(timezone.utc),
                 updated_at=datetime.now(timezone.utc),
             )
@@ -185,6 +187,7 @@ async def list_glossaries(
                     id=g.id,
                     name=g.name,
                     source_language=g.source_language or "fr",
+                    target_language=getattr(g, "target_language", None) or "en",
                     terms_count=len(g.terms) if g.terms else 0,
                     created_at=g.created_at,
                 )
@@ -339,6 +342,8 @@ async def update_glossary(
             if body.source_language is not None:
                 glossary.source_language = body.source_language
 
+            if body.target_language is not None:
+                glossary.target_language = body.target_language
             if body.terms is not None:
                 # Delete existing terms
                 session.query(GlossaryTerm).filter(