fix(webapp): keep the project section bottom padding constant when collapsing

The top section's bottom padding was pb-1 when collapsed and pb-2.5 when open, causing a vertical layout shift below the environment menu on toggle. Make it a constant pb-2.5 so only the horizontal padding animates.

Author: samejr

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

@@ -332,8 +332,8 @@ export function SideMenu({
         </div>
         <div
           className={cn(
-            "border-b border-grid-bright pt-1 transition-[padding] duration-200",
-            isCollapsed ? "pb-1 pl-1 pr-1" : "pb-2.5 pl-2.5 pr-2.5"
+            "border-b border-grid-bright pb-2.5 pt-1 transition-[padding] duration-200",
+            isCollapsed ? "pl-1 pr-1" : "pl-2.5 pr-2.5"
           )}
         >
           <div className="w-full space-y-1">