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/repository/event.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/shopspring/decimal"
 	"github.com/zitadel/logging"
 
 	"github.com/zitadel/zitadel/internal/eventstore"
@@ -22,7 +23,7 @@ type Event struct {
 	// Seq is the sequence of the event
 	Seq uint64
 	// Pos is the global sequence of the event multiple events can have the same sequence
-	Pos float64
+	Pos decimal.Decimal
 
 	//CreationDate is the time the event is created
 	// it's used for human readability.
@@ -97,7 +98,7 @@ func (e *Event) Sequence() uint64 {
 }
 
 // Position implements [eventstore.Event]
-func (e *Event) Position() float64 {
+func (e *Event) Position() decimal.Decimal {
 	return e.Pos
 }