[AutofillAi] AI features have enterprise icon

Problem: AutofillAi page should be available when the enterprise
feature is off. In this case, an enterprise icon should be displayed.

Solution: There are a couple of ways of implementing this. The most
obvious one would be to reuse the settings-toggle component directly,
however AI features have their enterprise information represented in a
standalone pref. On the the other hand, settings-toggle expects a
single pref, both that controls the feature and also has enterprise
data.

Because of this the decision was to reuse the existing "fake pref" that
AutofillAi has. It essentially extends it to also contain enterprise
pref data, therefore things work out of the box.

Screenshot: https://screenshot.googleplex.com/BfGupVZBf7LgX4r
Mocks: https://docs.google.com/presentation/d/13ME6mEoMmmrpwHsBDeV3kwyTaIxYHwdARafGhgbdKEA/edit?slide=id.g2af45484ef1_1_72&resourcekey=0-CLzUtm4o6vLiVYDDBEkFPg#slide=id.g2af45484ef1_1_72

Bug: 414779594
Change-Id: I15e92c6526ec8fbd2bcf664916fc047723a783ec
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6543095
Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Reviewed-by: Jan Keitel <jkeitel@google.com>
Commit-Queue: Bruno Braga <brunobraga@google.com>
Cr-Commit-Position: refs/heads/main@{#1466646}