Store Multistep Filter suggestion retention prefs

To support retention slice metrics logging, this change adds three user
Profile preferences in PrefService:
- Impression count: Incremented when a suggestion cue is first shown.
- Acceptance count: Incremented when a suggestion is accepted.
- Last action accepted: Boolean storing whether the ultimate outcome
of the previous suggestion impression was accepted.

Bug: b:527588776
Change-Id: I3c7b23e7809f15c28b647c6b4a6d9f3665801a36
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7999076
Reviewed-by: Jihad Hanna <jihadghanna@google.com>
Commit-Queue: Aditya Gupta <adigupt@google.com>
Cr-Commit-Position: refs/heads/main@{#1654101}