Add simple HanchuESS Helper

backend/src/main.py

@@ -6,6 +6,17 @@ app = FastAPI(title="HanchuESS Solar Backend API")
 def root():
     return {"message": "Welcome to the HanchuESS Solar Backend API!"}
 
+@app.get("/get_access_token", tags=["HanchuESS"])
+def get_access_token():
+    from service.hanchu_service import HanchuESSService
+
+    hanchu_service = HanchuESSService()
+    try:
+        access_token = hanchu_service.get_access_token()
+        return {"access_token": access_token}
+    except Exception as e:
+        return {"error": str(e)}
+
 if __name__ == "__main__":
     import uvicorn
     uvicorn.run(app, host="0.0.0.0", port=8050)