fix: restore logo in header with crumb-text layout

Logo img + crumb-text wrapper were missing from the breadcrumb.
Now: logo (32px) on left, $ protocol-droid and crumb path stacked
to its right.

frontend/index.html

@@ -15,9 +15,12 @@
 
 <header>
   <div class="breadcrumb" onclick="navigate('library')">
+    <img src="frontend/logo.svg" class="header-logo" alt="">
+    <div class="crumb-text">
       <span><span class="prompt">$</span> protocol-droid</span>
       <span class="crumb-path" id="crumbPath"></span>
     </div>
+  </div>
   <nav id="navBar">
     <a href="#library" class="active" data-view="library">PROTOCOLS</a>
     <a href="#collections" data-view="collections">COLLECTIONS</a>