Update README with LeetCode Daily Challenge

Author: jeremymanning

README.md

@@ -196,6 +196,7 @@ _**Note:** Our group is currently taking a break from grinding leetcode. The tab
 | December 30, 2024 | [2466](https://leetcode.com/problems/count-ways-to-build-good-strings/description/?envType=daily-question) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/2466) | 🟡 Medium |
 | December 31, 2024 | [983](https://leetcode.com/problems/minimum-cost-for-tickets/description/?envType=daily-question) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/983) | 🟡 Medium |
 | January 1, 2025 | [1422](https://leetcode.com/problems/maximum-score-after-splitting-a-string/description/?envType=daily-question) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/1422) | 🟢 Easy |
+| January 2, 2025 | [2559](https://leetcode.com/problems/count-vowel-strings-in-ranges/description/?envType=daily-question) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/2559) | 🟡 Medium |
 
 # Join our discussion!