Fix: Import FN field from vCard 4.0 when N field is missing

[Tchiller]

• Remove incorrect logic that treated FN as organization name
• Use FN field directly as contact name when N field is absent
• Fixes FN field is not imported from vCard 4.0 #465

Type of change(s)

• Bug fix
• Feature / enhancement
• Infrastructure / tooling (CI, build, deps, tests)
• Documentation

What changed and why

In vCard 4.0, FN is required but N is optional. Previously, contacts
with only FN field were incorrectly imported as organizations with
email addresses shown as the contact name.

Tests performed

I have successfully imported the three vCards which I will attach to this PR on my S22

Closes the following issue(s)

• Closes FN field is not imported from vCard 4.0 #465

Checklist

• I read the contribution guidelines.
• I manually tested my changes on device/emulator (if applicable).
• I updated the "Unreleased" section in CHANGELOG.md (if applicable).
• I have self-reviewed my pull request (no typos, formatting errors, etc.).
• I understand every change in this pull request.

[Tchiller]

My three test files:
test-contact-with-n-field.zip