feat: populate note files with problem descriptions and code stubs

Add populate-notes.mjs that fetches problem descriptions and
Python/C++ code stubs from LeetCode's GraphQL API. Populated
all 197 NeetCode 150 note files with:
- Problem description (examples, constraints)
- Python code stub (function signature)
- C++ code stub (function signature + includes)

API responses cached in leetcode/.cache/leetcode/ for instant re-runs.

org/study_deck_02/dsa/2-d-dynamic-programming/1143-longest-common-subsequence.org

@@ -1,18 +1,68 @@
 #+PROPERTY: STUDY_DECK_02
 * TODO 1143. Longest Common Subsequence :medium:
 :PROPERTIES:
-:NEETCODE: [[file:../../roadmap.org::*1143. Longest Common Subsequence][Roadmap]]
+:NEETCODE: [[file:../../roadmap.org::*1143. Longest Common Subsequence][1143. Longest Common Subsequence]]
 :END:
 
+Given two strings ~text1~ and ~text2~, return /the length of their longest *common subsequence*. /If there is no *common subsequence*, return ~0~.
+
+A *subsequence* of a string is a new string generated from the original string with some characters (can be none) deleted without changing the relative order of the remaining characters.
+
+ - For example, ~"ace"~ is a subsequence of ~"abcde"~.
+
+A *common subsequence* of two strings is a subsequence that is common to both strings.
+
+*Example 1:*
+
+
+#+begin_src
+Input: text1 = "abcde", text2 = "ace" 
+Output: 3  
+Explanation: The longest common subsequence is "ace" and its length is 3.
+#+end_src
+
+
+*Example 2:*
+
+
+#+begin_src
+Input: text1 = "abc", text2 = "abc"
+Output: 3
+Explanation: The longest common subsequence is "abc" and its length is 3.
+#+end_src
+
+
+*Example 3:*
+
+
+#+begin_src
+Input: text1 = "abc", text2 = "def"
+Output: 0
+Explanation: There is no such common subsequence, so the result is 0.
+#+end_src
+
+
+*Constraints:*
+
+ - ~1 <= text1.length, text2.length <= 1000~
+
+ - ~text1~ and ~text2~ consist of only lowercase English characters.
+
 ** TODO Approach
 Write your approach here.
 
 ** TODO Python
 #+begin_src python
-
+class Solution:
+    def longestCommonSubsequence(self, text1: str, text2: str) -> int:
 #+end_src
 
 ** TODO C++
 #+begin_src cpp
-
+class Solution {
+public:
+    int longestCommonSubsequence(string text1, string text2) {
+        
+    }
+};
 #+end_src