Initial commit MKD fixes

backend/migrations/create_user_roles.sql

@@ -0,0 +1,24 @@
+-- Миграция для создания таблицы ролей пользователей
+CREATE TABLE IF NOT EXISTS user_roles (
+  id         BIGSERIAL PRIMARY KEY,
+  user_id    TEXT NOT NULL,
+  role       VARCHAR(50) NOT NULL CHECK (role IN (
+    'manager', 
+    'finance_manager', 
+    'financier', 
+    'finance_director', 
+    'director', 
+    'top_management'
+  )),
+  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+  updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+  UNIQUE(user_id, role)
+);
+
+-- Индексы
+CREATE INDEX IF NOT EXISTS idx_user_roles_user_id ON user_roles(user_id);
+CREATE INDEX IF NOT EXISTS idx_user_roles_role ON user_roles(role);
+
+-- Комментарии
+COMMENT ON TABLE user_roles IS 'Роли пользователей для workflow согласования счетов';
+COMMENT ON COLUMN user_roles.role IS 'Роль: manager, finance_manager, financier, finance_director, director, top_management';