Adjust ACL behavior for "none" mode and make query cache optional

This commit allows skipping authentication, permission checks, and certain filters (e.g., deletions, expirations) when the ACL mode is set to "none" (open relay mode). It also introduces a configuration option to disable query caching to reduce memory usage. These changes improve operational flexibility for open relay setups and resource-constrained environments.

pkg/database/save-event.go

@@ -14,6 +14,7 @@ import (
 	"lol.mleku.dev/log"
 	"next.orly.dev/pkg/database/indexes"
 	"next.orly.dev/pkg/database/indexes/types"
+	"next.orly.dev/pkg/mode"
 	"git.mleku.dev/mleku/nostr/encoders/event"
 	"git.mleku.dev/mleku/nostr/encoders/filter"
 	"git.mleku.dev/mleku/nostr/encoders/hex"
@@ -177,13 +178,16 @@ func (d *D) SaveEvent(c context.Context, ev *event.E) (
 	}
 
 	// Check if the event has been deleted before allowing resubmission
-	if err = d.CheckForDeleted(ev, nil); err != nil {
-		// log.I.F(
-		// 	"SaveEvent: rejecting resubmission of deleted event ID=%s: %v",
-		// 	hex.Enc(ev.ID), err,
-		// )
-		err = fmt.Errorf("blocked: %s", err.Error())
-		return
+	// Skip deletion check when ACL is "none" (open relay mode)
+	if !mode.IsOpen() {
+		if err = d.CheckForDeleted(ev, nil); err != nil {
+			// log.I.F(
+			// 	"SaveEvent: rejecting resubmission of deleted event ID=%s: %v",
+			// 	hex.Enc(ev.ID), err,
+			// )
+			err = fmt.Errorf("blocked: %s", err.Error())
+			return
+		}
 	}
 	// check for replacement - only validate, don't delete old events
 	if kind.IsReplaceable(ev.Kind) || kind.IsParameterizedReplaceable(ev.Kind) {