fix: use role_map.get() to handle missing role keys safely

- Replace role_map[key] with role_map.get(key, key) to prevent KeyError
- Affects result_view and custom routes
- Ensures backward compatibility with old strategy data
- Fixes issue where strategies with unmapped roles cause page crashes

main.py

@@ -437,7 +437,7 @@ def custom_post():
 
     info = MVO.portfolio_info(np.array([1]), rets['Portfolio'].to_numpy().reshape(-1, 1), np.zeros(len(ret)-lookback))
     info['username'] = session.get('username').split('@')[0]
-    info['role'] = role_map[role]
+    info['role'] = role_map.get(role, role)
     info['id']='Custom data'
     info['name']='Custom data'
     info['date'] = '-'
@@ -547,7 +547,7 @@ def result_view():
     conn.close()
     # Processing data
     data = dict(data)
-    data['role'] = role_map[data['role']]
+    data['role'] = role_map.get(data['role'], data['role'])
     w = data['weight']
     r = data['ret']
     w = pd.DataFrame(w['data'], columns=w['columns'], index=w['index'])