fix(editor): keyboard tool shortcuts now actually switch the active tool

V/C/H key shortcuts called updateToolbarActive() which only updated button
visual state — Timeline.setTool() was never called so the cursor stayed on
the previous tool. Fix by calling Timeline.setTool() inside updateToolbarActive.

Also bump api.js reference to ?v=6 to match other pages.

services/web-ui/public/editor.html

@@ -387,7 +387,7 @@
   </div>
 </div>
 
-<script src="js/api.js"></script>
+<script src="js/api.js?v=6"></script>
 <script src="js/timecode.js"></script>
 <script src="js/timeline.js"></script>
 <script>
@@ -894,6 +894,7 @@ function updateToolbarActive(tool) {
     document.getElementById(map[k]).classList.remove('active');
   });
   if (map[tool]) document.getElementById(map[tool]).classList.add('active');
+  Timeline.setTool(tool);
 }
 
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