fix(dialog): apply CodeRabbit review suggestions

- VideoHelpDialog: call event.preventDefault() in escape handler so Reka does
  not auto-dismiss in parallel with the v-model close path
- Collapse :open + @update:open to v-model:open across migrated dialogs
- SecretFormDialog.test: reset captured handler via beforeEach

src/components/common/CustomizationDialog.vue

@@ -1,9 +1,5 @@
 <template>
-  <Dialog
-    :open="visible"
-    :modal="false"
-    @update:open="(open) => (visible = open)"
-  >
+  <Dialog v-model:open="visible" :modal="false">
     <DialogPortal>
       <DialogOverlay />
       <DialogContent

src/platform/assets/components/VideoHelpDialog.vue

@@ -1,5 +1,5 @@
 <template>
-  <Dialog :open="isVisible" @update:open="(open) => (isVisible = open)">
+  <Dialog v-model:open="isVisible">
     <DialogPortal>
       <DialogOverlay class="bg-black/70" />
       <DialogContent
@@ -56,8 +56,10 @@ const { videoUrl, ariaLabel = 'Help video' } = defineProps<{
 
 // The dialog mounts inside other dialogs (e.g. UploadModelFooter inside an
 // asset modal). Reka's Escape handling bubbles to the parent dialog and would
-// close it as well. Stop propagation so only this dialog closes.
+// close it as well. Stop propagation so only this dialog closes, and prevent
+// Reka's default auto-dismiss so the close path stays solely under the model.
 function onEscapeKeyDown(event: KeyboardEvent) {
+  event.preventDefault()
   event.stopPropagation()
   isVisible.value = false
 }

src/platform/secrets/components/SecretFormDialog.test.ts

@@ -1,5 +1,5 @@
 import { render } from '@testing-library/vue'
-import { describe, expect, it, vi } from 'vitest'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
 import { defineComponent } from 'vue'
 import { createI18n } from 'vue-i18n'
 
@@ -80,8 +80,11 @@ vi.mock('@/components/ui/dialog/DialogClose.vue', () => ({
 const i18n = createI18n({ legacy: false, locale: 'en', messages: { en: {} } })
 
 describe('SecretFormDialog', () => {
-  it('prevents backdrop pointer-down-outside from closing the dialog', () => {
+  beforeEach(() => {
     capturedPointerDownOutside = null
+  })
+
+  it('prevents backdrop pointer-down-outside from closing the dialog', () => {
     render(SecretFormDialog, {
       global: { plugins: [i18n] },
       props: { visible: true }

src/platform/secrets/components/SecretFormDialog.vue

@@ -1,5 +1,5 @@
 <template>
-  <Dialog :open="visible" @update:open="(open) => (visible = open)">
+  <Dialog v-model:open="visible">
     <DialogPortal>
       <DialogOverlay />
       <DialogContent