Proposal: Add modern `Promise.allSettled` alternative to "Fetch users" task solution

Description

The current solution for the "Fetch users from GitHub" task demonstrates parallel execution by mixing .then() with async/await. While this serves its stated pedagogical purpose, modern JavaScript codebases typically utilize pure async/await combined with Promise.allSettled for concurrent, fault-tolerant network requests.

Proposal

I propose adding a brief "Alternative modern approach" section to the bottom of the solution.md file. This addition will demonstrate how to achieve the same concurrent execution and error handling using Promise.allSettled and asynchronous array mapping, without removing the original lesson.

閱讀 5-network/01-fetch/01-fetch-users/solution.md，以及其中連結的 task.md 和現有的 solution。在保留原始課程的同時，新增一個簡短的「現代替代方案」段落，使用 Promise.allSettled、async/await 和非同步陣列映射示範並行且容錯的請求。範例清楚、與 task 一致，並記錄在 solution 檔案中，即表示完成。