More string lint checks.

Expand strings into samples that are representative of what'll be
shown in UI, and warn if they're longer than defined CHAR LIMIT.

Guide all-caps strings towards android:textAllCaps if actions.

Warn when strings mention "phone" without defining product-specific
variants.

Bug: 76097999
Test: manual
Change-Id: I08046ecf531b2d616cb357639e804b73d6a12bea