docs: add missing comments in readme

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---

Author: Om-A-osc

lib/node_modules/@stdlib/stats/strided/snancount/README.md

@@ -152,18 +152,24 @@ console.log( v );
 
 <!-- /.examples -->
 
+<!-- C interface documentation. -->
+
 * * *
 
 <section class="c">
 
 ## C APIs
 
+<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
+
 <section class="intro">
 
 </section>
 
 <!-- /.intro -->
 
+<!-- C usage documentation. -->
+
 <section class="usage">
 
 ### Usage
@@ -219,6 +225,10 @@ CBLAS_INT stdlib_strided_snancount_ndarray( const CBLAS_INT N, const float *X, c
 
 <!-- /.usage -->
 
+
+<!-- C API usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+
 <section class="notes">
 
 ### Notes
@@ -229,13 +239,14 @@ CBLAS_INT stdlib_strided_snancount_ndarray( const CBLAS_INT N, const float *X, c
 
 <!-- /.notes -->
 
+<!-- C API usage examples. -->
+
 <section class="examples">
 
 ### Examples
 
 ```c
 #include "stdlib/stats/strided/snancount.h"
-#include <stdint.h>
 #include <stdio.h>
 
 int main( void ) {