fix: use div instead of DisclosureButton for decls in the module tree (…

…#2587)

This fixes a `Cannot read properties of undefined (reading 'length')`
error that was appearing every time you went to the modules page, which
was coming from inside `DisclosureButton`. The error's stack trace was
minified beyond comprehension, but I'm guessing it was because this was
a malformed usage of `DisclosureButton` - not wrapped in a corresponding
`Disclosure` (its parent `Disclosure` component mapped to the higher
level module buttons, not the decl items).

frontend/console/e2e/verb.spec.ts

@@ -7,7 +7,7 @@ ftlTest.beforeEach(async ({ page }) => {
   const moduleEcho = page.getByRole('button', { name: 'echo' })
   await moduleEcho.click()
 
-  const verbEcho = page.getByRole('button', { name: 'echo Exported' })
+  const verbEcho = page.locator('div#decl-echo')
   await verbEcho.click()
 
   await expect(page).toHaveURL(/\/modules\/echo\/verb\/echo/)

frontend/console/src/features/modules/ModulesTree.tsx

@@ -50,10 +50,11 @@ const DeclNode = ({ decl, href, isSelected }: { decl: Decl; href: string; isSele
   const Icon = useMemo(() => icons[decl.value.case || ''] || CodeBracketSquareIcon, [decl.value.case])
   return (
     <li className='my-1'>
-      <DisclosureButton
+      <div
+        id={`decl-${decl.value.value.name}`}
         className={classNames(
           isSelected ? 'bg-gray-200 dark:bg-gray-700 hover:bg-gray-300 hover:dark:bg-gray-600' : 'hover:bg-gray-200 hover:dark:bg-gray-700',
-          'group flex items-center gap-x-2 rounded-md pl-4 pr-2 text-sm font-light leading-6 w-full',
+          'group flex items-center gap-x-2 rounded-md pl-4 pr-2 text-sm font-light leading-6 w-full cursor-pointer',
         )}
         onClick={(e) => {
           e.preventDefault()
@@ -63,7 +64,7 @@ const DeclNode = ({ decl, href, isSelected }: { decl: Decl; href: string; isSele
         <Icon aria-hidden='true' className='size-4 shrink-0' />
         {decl.value.value.name}
         {(decl.value.value as WithExport).export === true ? <ExportBadge /> : []}
-      </DisclosureButton>
+      </div>
     </li>
   )
 }