🩹(frontend) fix circular imports in Dialog and Form primitives

While attempting to lazy-load routes, Vite/Rollup warnings revealed
that the Dialog and Form primitives were causing circular imports
through their use of the barrel file.

Easy to address: when using primitive elements inside those
primitives, rely on direct imports instead of the barrel file.

src/frontend/src/primitives/Dialog.tsx

@@ -8,7 +8,10 @@ import {
   type DialogProps as RACDialogProps,
   Heading,
 } from 'react-aria-components'
-import { Div, Button, Box, VerticallyOffCenter } from '@/primitives'
+import { Div } from './Div'
+import { Button } from './Button'
+import { Box } from './Box'
+import { VerticallyOffCenter } from './VerticallyOffCenter'
 import { text } from './Text'
 import { MutableRefObject } from 'react'
 import { css } from '@/styled-system/css'

src/frontend/src/primitives/Form.tsx

@@ -2,8 +2,8 @@ import { type FormEvent } from 'react'
 import { Form as RACForm, type FormProps } from 'react-aria-components'
 import { useTranslation } from 'react-i18next'
 import { HStack } from '@/styled-system/jsx'
-import { Button, useCloseDialog } from '@/primitives'
-import { type ButtonProps } from '@/primitives/Button'
+import { useCloseDialog } from './useCloseDialog'
+import { type ButtonProps, Button } from './Button'
 
 /**
  * From wrapper that exposes form data on submit and adds submit/cancel buttons