Update README with LeetCode Daily Challenge

Author: jeremymanning

README.md

@@ -50,6 +50,7 @@ This means you'll always find an AI-generated solution to compare with or learn
 | March 28, 2026 | [2573](https://leetcode.com/problems/find-the-string-with-lcp/description/?envType=daily-question) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/2573) | 🔴 Hard |
 | March 29, 2026 | [2839](https://leetcode.com/problems/check-if-strings-can-be-made-equal-with-operations-i/description/?envType=daily-question) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/2839) | 🟢 Easy |
 | March 30, 2026 | [2840](https://leetcode.com/problems/check-if-strings-can-be-made-equal-with-operations-ii/description/?envType=daily-question) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/2840) | 🟡 Medium |
+| March 31, 2026 | [3474](https://leetcode.com/problems/lexicographically-smallest-generated-string/description/?envType=daily-question) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/3474) | 🔴 Hard |
 
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