ContactDetails: "TypeError: this.localContact is undefined"

[ChristophWurst]

Describe the bug

App throws an error because the localContact is undefined at component creation time and used in a computed prop without an undefined check

Steps to reproduce

1. Add contacts
2. Reload the page
3. Watch the console

Expected behavior

No errors

Actual behavior

[Vue warn]: Error in render: "TypeError: this.localContact is undefined"

found in

---> <DetailsHeader> at src/components/DetailsHeader.vue
       <NcAppContentDetails>
         <ContactDetails> at src/components/ContactDetails.vue
           <NcAppContent>
             <ContactsContent> at src/components/AppContent/ContactsContent.vue
               <Content>
                 <Contacts> at src/views/Contacts.vue
                   <ContactsRoot> at src/ContactsRoot.vue
                     <Root>

and

TypeError: this.localContact is undefined
    excludeFromBirthdayLabel ContactDetails.vue:486
    VueJS 4
    fn ContactDetails.vue:319
    VueJS 2
    render DetailsHeader.vue:49
    node_modules contacts-main.js:41941
vue.runtime.esm.js:1897

Contact version

4

Operating system

No response

PHP engine version

None

Web server

None

Database

None

Additional info

Likely introduced with #3009.

👀 @sylvainmetayer