fix(eventstore): use decimal, correct mirror (#9914)

# 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

---------

Co-authored-by: Livio Spring <livio.a@gmail.com>

internal/eventstore/v3/event.go

@@ -6,6 +6,7 @@ import (
 	"strconv"
 	"time"
 
+	"github.com/shopspring/decimal"
 	"github.com/zitadel/logging"
 
 	"github.com/zitadel/zitadel/internal/api/authz"
@@ -42,7 +43,7 @@ type event struct {
 	command   *command
 	createdAt time.Time
 	sequence  uint64
-	position  float64
+	position  decimal.Decimal
 }
 
 // TODO: remove on v3
@@ -152,8 +153,8 @@ func (e *event) Sequence() uint64 {
 	return e.sequence
 }
 
-// Sequence implements [eventstore.Event]
-func (e *event) Position() float64 {
+// Position implements [eventstore.Event]
+func (e *event) Position() decimal.Decimal {
 	return e.position
 }