feat: display every focusable part

index.html

@@ -113,7 +113,7 @@
         </section>
         <section class="stability">
           <ul class="stability-list focusable">
-            <li class="s5s focusable">
+            <li class="5s focusable">
               <!-- <a href="/5s.html">5S</a> -->
               5S
             </li>
@@ -144,6 +144,9 @@
           <code>focus</code>: focus only
           <a href="?focus=pull-system">a part</a> of the TPS. Can be
           <a href="?focus=pull-system&focus=andon&focus=quality">multiple</a>.
+          (Here are all the possible values:
+          <span id="focus-list"></span>
+          )
         </li>
         <li>
           <code>text</code>: <a href="?text=hide">hide</a> text to only have the