Feat: add new Markdown parser (#39800)

and change all the challenges to new `md` format.

curriculum/challenges/english/10-coding-interview-prep/rosetta-code/sum-of-squares.md

@@ -5,49 +5,57 @@ challengeType: 5
 forumTopicId: 302334
 ---
 
-## Description
-
-<section id='description'>
+# --description--
 
 Write a function to find the sum of squares of an array of integers.
 
-</section>
+# --hints--
 
-## Instructions
+`sumsq` should be a function.
 
-<section id='instructions'>
-
-</section>
-
-## Tests
-
-<section id='tests'>
-
-```yml
-tests:
-  - text: <code>sumsq</code> should be a function.
-    testString: assert(typeof sumsq == 'function');
-  - text: <code>sumsq([1, 2, 3, 4, 5])</code> should return a number.
-    testString: assert(typeof sumsq([1, 2, 3, 4, 5]) == 'number');
-  - text: <code>sumsq([1, 2, 3, 4, 5])</code> should return <code>55</code>.
-    testString: assert.equal(sumsq([1, 2, 3, 4, 5]), 55);
-  - text: <code>sumsq([25, 32, 12, 7, 20])</code> should return <code>2242</code>.
-    testString: assert.equal(sumsq([25, 32, 12, 7, 20]), 2242);
-  - text: <code>sumsq([38, 45, 35, 8, 13])</code> should return <code>4927</code>.
-    testString: assert.equal(sumsq([38, 45, 35, 8, 13]), 4927);
-  - text: <code>sumsq([43, 36, 20, 34, 24])</code> should return <code>5277</code>.
-    testString: assert.equal(sumsq([43, 36, 20, 34, 24]), 5277);
-  - text: <code>sumsq([12, 33, 26, 18, 1, 16, 3])</code> should return <code>2499</code>.
-    testString: assert.equal(sumsq([12, 33, 26, 18, 1, 16, 3]), 2499);
+```js
+assert(typeof sumsq == 'function');
 ```
 
-</section>
+`sumsq([1, 2, 3, 4, 5])` should return a number.
 
-## Challenge Seed
+```js
+assert(typeof sumsq([1, 2, 3, 4, 5]) == 'number');
+```
 
-<section id='challengeSeed'>
+`sumsq([1, 2, 3, 4, 5])` should return `55`.
 
-<div id='js-seed'>
+```js
+assert.equal(sumsq([1, 2, 3, 4, 5]), 55);
+```
+
+`sumsq([25, 32, 12, 7, 20])` should return `2242`.
+
+```js
+assert.equal(sumsq([25, 32, 12, 7, 20]), 2242);
+```
+
+`sumsq([38, 45, 35, 8, 13])` should return `4927`.
+
+```js
+assert.equal(sumsq([38, 45, 35, 8, 13]), 4927);
+```
+
+`sumsq([43, 36, 20, 34, 24])` should return `5277`.
+
+```js
+assert.equal(sumsq([43, 36, 20, 34, 24]), 5277);
+```
+
+`sumsq([12, 33, 26, 18, 1, 16, 3])` should return `2499`.
+
+```js
+assert.equal(sumsq([12, 33, 26, 18, 1, 16, 3]), 2499);
+```
+
+# --seed--
+
+## --seed-contents--
 
 ```js
 function sumsq(array) {
@@ -55,12 +63,7 @@ function sumsq(array) {
 }
 ```
 
-</div>
-</section>
-
-## Solution
-
-<section id='solution'>
+# --solutions--
 
 ```js
 function sumsq(array) {
@@ -73,5 +76,3 @@ function sumsq(array) {
   return sum;
 }
 ```
-
-</section>