Update README with LeetCode Daily Challenge

Author: jeremymanning

README.md

@@ -48,6 +48,7 @@ This means you'll always find an AI-generated solution to compare with or learn
 | July 26, 2026 | [628](https://leetcode.com/problems/maximum-product-of-three-numbers/description/?envType=daily-question) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/628) | 🟢 Easy |
 | July 27, 2026 | [1464](https://leetcode.com/problems/maximum-product-of-two-elements-in-an-array/description/?envType=daily-question) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/1464) | 🟢 Easy |
 | July 28, 2026 | [3517](https://leetcode.com/problems/smallest-palindromic-rearrangement-i/description/?envType=daily-question) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/3517) | 🟡 Medium |
+| July 29, 2026 | [3518](https://leetcode.com/problems/smallest-palindromic-rearrangement-ii/description/?envType=daily-question) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/3518) | 🔴 Hard |
 
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