feat: add debug events API (#8533)

# Which Problems Are Solved

Add a debug API which allows pushing a set of events to be reduced in a
dedicated projection.
The events can carry a sleep duration which simulates a slow query
during projection handling.

# How the Problems Are Solved

- `CreateDebugEvents` allows pushing multiple events which simulate the
lifecycle of a resource. Each event has a `projectionSleep` field, which
issues a `pg_sleep()` statement query in the projection handler :
  - Add
  - Change
  - Remove
- `ListDebugEventsStates` list the current state of the projection,
optionally with a Trigger
- `GetDebugEventsStateByID` get the current state of the aggregate ID in
the projection, optionally with a Trigger


# Additional Changes

- none

# Additional Context

-  Allows reproduction of https://github.com/zitadel/zitadel/issues/8517

internal/repository/debug_events/aggregate.go

@@ -0,0 +1,27 @@
+package debug_events
+
+import (
+	"github.com/zitadel/zitadel/internal/eventstore"
+)
+
+const (
+	eventTypePrefix = eventstore.EventType("debug.")
+)
+
+const (
+	AggregateType    = "debug"
+	AggregateVersion = "v1"
+)
+
+type Aggregate struct {
+	eventstore.Aggregate
+}
+
+func NewAggregate(id, resourceOwner string) *eventstore.Aggregate {
+	return &eventstore.Aggregate{
+		Type:          AggregateType,
+		Version:       AggregateVersion,
+		ID:            id,
+		ResourceOwner: resourceOwner,
+	}
+}