feat(eventstore): increase parallel write capabilities (#5940)

This implementation increases parallel write capabilities of the eventstore.
Please have a look at the technical advisories: [05](https://zitadel.com/docs/support/advisory/a10005) and  [06](https://zitadel.com/docs/support/advisory/a10006).
The implementation of eventstore.push is rewritten and stored events are migrated to a new table `eventstore.events2`.
If you are using cockroach: make sure that the database user of ZITADEL has `VIEWACTIVITY` grant. This is used to query events.

cmd/setup/14.go

@@ -0,0 +1,72 @@
+package setup
+
+import (
+	"context"
+	"database/sql"
+	"embed"
+	"errors"
+	"strings"
+
+	"github.com/jackc/pgconn"
+	"github.com/zitadel/logging"
+
+	"github.com/zitadel/zitadel/internal/database"
+)
+
+var (
+	//go:embed 14/cockroach/*.sql
+	//go:embed 14/postgres/*.sql
+	newEventsTable embed.FS
+)
+
+type NewEventsTable struct {
+	dbClient *database.DB
+}
+
+func (mig *NewEventsTable) Execute(ctx context.Context) error {
+	migrations, err := newEventsTable.ReadDir("14/" + mig.dbClient.Type())
+	if err != nil {
+		return err
+	}
+	// if events already exists events2 is created during a setup job
+	var count int
+	err = mig.dbClient.QueryRow(
+		func(row *sql.Row) error {
+			if err = row.Scan(&count); err != nil {
+				return err
+			}
+			return row.Err()
+		},
+		"SELECT count(*) FROM information_schema.tables WHERE table_schema = 'eventstore' AND table_name like 'events2'",
+	)
+	if err != nil || count == 1 {
+		return err
+	}
+	for _, migration := range migrations {
+		stmt, err := readStmt(newEventsTable, "14", mig.dbClient.Type(), migration.Name())
+		if err != nil {
+			return err
+		}
+		stmt = strings.ReplaceAll(stmt, "{{.username}}", mig.dbClient.Username())
+
+		logging.WithFields("migration", mig.String(), "file", migration.Name()).Debug("execute statement")
+
+		_, err = mig.dbClient.ExecContext(ctx, stmt)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (mig *NewEventsTable) String() string {
+	return "14_events_push"
+}
+
+func (mig *NewEventsTable) ContinueOnErr(err error) bool {
+	pgErr := new(pgconn.PgError)
+	if errors.As(err, &pgErr) {
+		return pgErr.Code == "42P01"
+	}
+	return false
+}