Fix admin login endpoint to accept JSON instead of form data

frontend/src/app/admin/login/page.tsx

@@ -40,7 +40,8 @@ function AdminLoginContent() {
       const redirect = searchParams.get("redirect") || "/admin";
       router.push(redirect);
     } catch (err: any) {
-      setError(err.message || "Erreur de connexion");
+      const errorMessage = typeof err.message === 'string' ? err.message : "Erreur de connexion";
+      setError(errorMessage);
     } finally {
       setLoading(false);
     }

main.py

@@ -8,6 +8,7 @@ from fastapi.responses import FileResponse, JSONResponse
 from fastapi.middleware.cors import CORSMiddleware
 from fastapi.staticfiles import StaticFiles
 from fastapi.security import HTTPBasic, HTTPBasicCredentials
+from pydantic import BaseModel
 from contextlib import asynccontextmanager
 from pathlib import Path
 from typing import Optional
@@ -858,20 +859,16 @@ async def reconstruct_document(
 
 # ============== SaaS Management Endpoints ==============
 
+class AdminLoginRequest(BaseModel):
+    password: str
+
 @app.post("/admin/login")
-async def admin_login(
-    username: str = Form(...),
-    password: str = Form(...)
-):
+async def admin_login(request: AdminLoginRequest):
     """
     Admin login endpoint
     Returns a bearer token for authenticated admin access
     """
-    if username != ADMIN_USERNAME:
-        logger.warning(f"Failed admin login attempt with username: {username}")
-        raise HTTPException(status_code=401, detail="Invalid credentials")
-    
-    if not verify_admin_password(password):
+    if not verify_admin_password(request.password):
         logger.warning(f"Failed admin login attempt - wrong password")
         raise HTTPException(status_code=401, detail="Invalid credentials")
     
@@ -880,7 +877,8 @@ async def admin_login(
     
     return {
         "status": "success",
-        "token": token,
+        "access_token": token,
+        "token_type": "bearer",
         "expires_in": 86400,  # 24 hours in seconds
         "message": "Login successful"
     }