Add dbmate migrations to match state with `self-host/migrations/v0.10.x-read-optim.sh`

[anupcowkur]

Running dbmate migrate currently results in a clickhouse db state that misses the migrations introduced in self-host/migrations/v0.10.x-read-optim.sh. We need to add those so that running dbmate migrations can bring db up to expected state without having to run the shell script.

This is useful for fresh installs, test setups and for installs where db is at an older state and wants to get up to latest state without caring for data loss.

The new migrations need to idempotent and only do modifications if they are not already done so that these migrations are safe to run on databases to which the shell script has already been applied.