feat(chat): save and view chat history — admin-only saved_chats, History page, open-a-chat return

app/main.py

@@ -21,6 +21,7 @@ from starlette.middleware.sessions import SessionMiddleware
 
 from app.api.auth import router as auth_router
 from app.api.chat import router as chat_router
+from app.api.chats import router as chats_router
 from app.api.config import router as config_router
 from app.api.docs import router as docs_router
 from app.api.git_sources import router as git_sources_router
@@ -71,6 +72,7 @@ def create_app() -> FastAPI:
     app.include_router(chat_router, prefix="/api")
     app.include_router(steering_router, prefix="/api")
     app.include_router(sync_router, prefix="/api")
+    app.include_router(chats_router, prefix="/api")
 
     # Cache busting (phase 33): the five HTML pages revalidate (no-cache)
     # with ?v=<token> asset refs; /assets/* becomes immutable for a year.