fix(eventstore): use decimal, correct mirror (#9916)

# Eventstore fixes

- `event.Position` used float64 before which can lead to [precision
loss](https://github.com/golang/go/issues/47300). The type got replaced
by [a type without precision
loss](https://github.com/jackc/pgx-shopspring-decimal)
- the handler reported the wrong error if the current state was updated
and therefore took longer to retry failed events.

# Mirror fixes

- max age of auth requests can be configured to speed up copying data
from `auth.auth_requests` table. Auth requests last updated before the
set age will be ignored. Default is 1 month
- notification projections are skipped because notifications should be
sent by the source system. The projections are set to the latest
position
- ensure that mirror can be executed multiple times

cmd/mirror/event.go

@@ -3,6 +3,8 @@ package mirror
 import (
 	"context"
 
+	"github.com/shopspring/decimal"
+
 	"github.com/zitadel/zitadel/internal/v2/eventstore"
 	"github.com/zitadel/zitadel/internal/v2/readmodel"
 	"github.com/zitadel/zitadel/internal/v2/system"
@@ -29,7 +31,7 @@ func queryLastSuccessfulMigration(ctx context.Context, destinationES *eventstore
 	return lastSuccess, nil
 }
 
-func writeMigrationSucceeded(ctx context.Context, destinationES *eventstore.EventStore, id, source string, position float64) error {
+func writeMigrationSucceeded(ctx context.Context, destinationES *eventstore.EventStore, id, source string, position decimal.Decimal) error {
 	return destinationES.Push(
 		ctx,
 		eventstore.NewPushIntent(