fix(ui): undefined operators for virtual field with unsupported field types (#13820)

### What?

Fixes crash when virtual fields use field types not supported by the
WhereBuilder (e.g. 'group' fields).

<img width="1336" height="459" alt="Screenshot 2025-09-16 at 11 00
30 AM"
src="https://github.com/user-attachments/assets/3adbb507-3033-4f52-b7cc-3c5bad74900b"
/>

### Why?

Users reported a crash with error "Cannot read properties of undefined
(reading 'operators')" when entering collection list views with virtual
fields that have `type: 'group'`. The issue occurred because:
- Virtual fields can use any field type including 'group'
- The `fieldTypes` object in WhereBuilder only supports specific field
types (text, number, select, etc.)
- Code tried to access `fieldTypes[field.type].operators` when
`field.type` was 'group', causing undefined access

### How?

- Refactored virtual field handling to use a unified processing flow
instead of separate early returns
- Virtual fields now set the `pathPrefix` to their virtual path and
continue through normal field validation

---
- To see the specific tasks where the Asana app for GitHub is being
used, see below:
  - https://app.asana.com/0/0/1211315667956059

---------

Co-authored-by: Jarrod Flesch <jarrodmflesch@gmail.com>

packages/ui/src/forms/Form/createNestedClientFieldPath.ts

@@ -5,7 +5,7 @@ import { fieldAffectsData } from 'payload/shared'
 
 export const createNestedClientFieldPath = (parentPath: string, field: ClientField): string => {
   if (parentPath) {
-    if (fieldAffectsData(field)) {
+    if (fieldAffectsData(field) && field.name) {
       return `${parentPath}.${field.name}`
     }
     return parentPath

packages/ui/src/utilities/reduceFieldsToOptions.tsx

@@ -26,9 +26,10 @@ export const reduceFieldsToOptions = ({
   fields,
   i18n,
   labelPrefix,
-  pathPrefix,
+  pathPrefix: pathPrefixFromArgs,
 }: ReduceFieldOptionsArgs): ReducedField[] => {
   return fields.reduce((reduced, field) => {
+    let pathPrefix = pathPrefixFromArgs
     // Do not filter out `field.admin.disableListFilter` fields here, as these should still render as disabled if they appear in the URL query
     // Filter out `virtual: true` fields since they are regular virtuals and not backed by a DB field
     if (
@@ -40,18 +41,11 @@ export const reduceFieldsToOptions = ({
 
     // Handle virtual:string fields (virtual relationships, e.g. "post.title")
     if ('virtual' in field && typeof field.virtual === 'string') {
-      const baseLabel = ('label' in field && field.label) || ('name' in field && field.name) || ''
-      const localizedLabel = getTranslation(baseLabel, i18n)
-
-      reduced.push({
-        label: localizedLabel,
-        plainTextLabel: localizedLabel,
-        value: field.virtual, // e.g. "post.title"
-        ...fieldTypes[field.type],
-        field,
-        operators: fieldTypes[field.type].operators,
-      })
-      return reduced
+      pathPrefix = pathPrefix ? pathPrefix + '.' + field.virtual : field.virtual
+      if (fieldAffectsData(field)) {
+        // ignore virtual field names
+        field.name = ''
+      }
     }
 
     if (field.type === 'tabs' && 'tabs' in field) {