feat: add cache-control:no-cache while sending file and index

src/server.rs

@@ -838,6 +838,8 @@ impl Server {
                 }
             }
 
+            res.headers_mut()
+                .typed_insert(CacheControl::new().with_no_cache());
             res.headers_mut().typed_insert(last_modified);
             res.headers_mut().typed_insert(etag.clone());
 
@@ -958,6 +960,8 @@ impl Server {
             .replace("__INDEX_DATA__", &index_data);
         res.headers_mut()
             .typed_insert(ContentLength(output.as_bytes().len() as u64));
+        res.headers_mut()
+            .typed_insert(CacheControl::new().with_no_cache());
         if head_only {
             return Ok(());
         }