Fix uid map to be simpler and fix partial bucket.

The previous scheme captured periodic snapshots for each config with
complex logic that's unnecessary and wasted memory. We actually don't
need to store any snapshots since we just convert the current state
into a snapshot and also include the deltas (change events) since the
previous report until now.

To make the system more robust, we also include up to 100 of the
deleted apps in the uid map.

Also, fix the wiring of the partial buckets so the metric producers
form partial buckets on both app upgrade and removal, but not on
installation of a new app.

Also, we update StatsCompanionService to also include disabled apps.

Bug: 77607583
Test: Verified unit-tests pass and added new e2e tests.
Change-Id: I98e1f544d6e6571545ae1581c4cebab807596f51