fix(webapp): only render the Help & Feedback chevron when expanded

The disclosure chevron is a hover affordance with no meaning in the
collapsed rail, but it was left mounted there. Rendering it only when the
side menu is expanded keeps the collapsed icon clean and stops the chevron
slot from affecting the collapsed button's layout or paint.

Author: samejr

apps/webapp/app/components/navigation/HelpAndFeedbackPopover.tsx

@@ -85,17 +85,16 @@ export function HelpAndFeedback({
                       Help & Feedback
                     </span>
                   </span>
-                  {/* Up/down chevron revealed on hover, matching the Project menu button. */}
-                  <span
-                    className={cn(
-                      "overflow-hidden transition-[max-width] duration-200",
-                      isCollapsed
-                        ? "max-w-0 opacity-0"
-                        : "max-w-[16px] opacity-0 group-hover:opacity-100"
-                    )}
-                  >
-                    <DropdownIcon className="size-4 min-w-4 text-text-dimmed group-hover:text-text-bright" />
-                  </span>
+                  {/*
+                    Up/down chevron revealed on hover, matching the Project menu button. Only
+                    rendered when expanded so it can never occupy space or paint over the
+                    collapsed icon (it is a hover affordance that has no meaning collapsed).
+                  */}
+                  {!isCollapsed && (
+                    <span className="overflow-hidden transition-[max-width] duration-200 max-w-[16px] opacity-0 group-hover:opacity-100">
+                      <DropdownIcon className="size-4 min-w-4 text-text-dimmed group-hover:text-text-bright" />
+                    </span>
+                  )}
                 </PopoverTrigger>
               }
               content={