feat: add NIP-77 negentropy sync support

Add support for NIP-77 (Negentropy Syncing) protocol messages using
the negentropy-kmp library for efficient set reconciliation between
client and relay.

New files:
- NegOpenCmd, NegMsgCmd, NegCloseCmd: Client-to-relay commands
- NegMsgMessage, NegErrMessage: Relay-to-client messages
- NegentropySession: Client-side reconciliation orchestrator
- NegentropyServerSession: Server-side reconciliation handler
- NegentropyManager: High-level sync manager with listener callbacks

Updated serializers:
- Jackson MessageSerializer/Deserializer for NEG-MSG, NEG-ERR
- Jackson CommandSerializer/Deserializer for NEG-OPEN, NEG-MSG, NEG-CLOSE
- Kotlin MessageKSerializer/CommandKSerializer for all NIP-77 types

Compatible with strfry relay's negentropy implementation via the
negentropy-kmp library which implements the same Protocol V1 spec.

https://claude.ai/code/session_01Dc6W1G1jURAAR9kzyVvk6g

quartz/src/jvmAndroid/kotlin/com/vitorpamplona/quartz/nip01Core/relay/commands/toClient/MessageDeserializer.kt

@@ -26,6 +26,8 @@ import com.fasterxml.jackson.databind.DeserializationContext
 import com.fasterxml.jackson.databind.JsonNode
 import com.fasterxml.jackson.databind.deser.std.StdDeserializer
 import com.vitorpamplona.quartz.nip01Core.jackson.EventDeserializer
+import com.vitorpamplona.quartz.nip77Negentropy.NegErrMessage
+import com.vitorpamplona.quartz.nip77Negentropy.NegMsgMessage
 
 class MessageDeserializer : StdDeserializer<Message>(Message::class.java) {
     val eventDeserializer = EventDeserializer()
@@ -101,6 +103,20 @@ class MessageDeserializer : StdDeserializer<Message>(Message::class.java) {
                     )
                 }
 
+                NegMsgMessage.LABEL -> {
+                    NegMsgMessage(
+                        subId = jp.nextTextValue(),
+                        message = jp.nextTextValue(),
+                    )
+                }
+
+                NegErrMessage.LABEL -> {
+                    NegErrMessage(
+                        subId = jp.nextTextValue(),
+                        reason = jp.nextTextValue() ?: "",
+                    )
+                }
+
                 else -> {
                     throw IllegalArgumentException("Message $type is not supported")
                 }

quartz/src/jvmAndroid/kotlin/com/vitorpamplona/quartz/nip01Core/relay/commands/toClient/MessageSerializer.kt

@@ -24,6 +24,8 @@ import com.fasterxml.jackson.core.JsonGenerator
 import com.fasterxml.jackson.databind.SerializerProvider
 import com.fasterxml.jackson.databind.ser.std.StdSerializer
 import com.vitorpamplona.quartz.nip01Core.jackson.EventSerializer
+import com.vitorpamplona.quartz.nip77Negentropy.NegErrMessage
+import com.vitorpamplona.quartz.nip77Negentropy.NegMsgMessage
 
 class MessageSerializer : StdSerializer<Message>(Message::class.java) {
     val eventSerializer = EventSerializer()
@@ -75,6 +77,16 @@ class MessageSerializer : StdSerializer<Message>(Message::class.java) {
             is EoseMessage -> {
                 gen.writeString(msg.subId)
             }
+
+            is NegMsgMessage -> {
+                gen.writeString(msg.subId)
+                gen.writeString(msg.message)
+            }
+
+            is NegErrMessage -> {
+                gen.writeString(msg.subId)
+                gen.writeString(msg.reason)
+            }
         }
 
         gen.writeEndArray()

quartz/src/jvmAndroid/kotlin/com/vitorpamplona/quartz/nip01Core/relay/commands/toRelay/CommandDeserializer.kt

@@ -29,6 +29,9 @@ import com.vitorpamplona.quartz.nip01Core.jackson.EventDeserializer
 import com.vitorpamplona.quartz.nip01Core.relay.filters.Filter
 import com.vitorpamplona.quartz.nip01Core.relay.filters.ManualFilterDeserializer
 import com.vitorpamplona.quartz.nip42RelayAuth.RelayAuthEvent
+import com.vitorpamplona.quartz.nip77Negentropy.NegCloseCmd
+import com.vitorpamplona.quartz.nip77Negentropy.NegMsgCmd
+import com.vitorpamplona.quartz.nip77Negentropy.NegOpenCmd
 
 class CommandDeserializer : StdDeserializer<Command>(Command::class.java) {
     val eventDeserializer = EventDeserializer()
@@ -97,6 +100,33 @@ class CommandDeserializer : StdDeserializer<Command>(Command::class.java) {
                     )
                 }
 
+                NegOpenCmd.LABEL -> {
+                    val subId = jp.nextTextValue()
+                    jp.nextToken()
+                    val filterObj: ObjectNode = jp.codec.readTree(jp)
+                    val filter = ManualFilterDeserializer.fromJson(filterObj)
+                    val initialMessage = jp.nextTextValue()
+
+                    NegOpenCmd(
+                        subId = subId,
+                        filter = filter,
+                        initialMessage = initialMessage,
+                    )
+                }
+
+                NegMsgCmd.LABEL -> {
+                    NegMsgCmd(
+                        subId = jp.nextTextValue(),
+                        message = jp.nextTextValue(),
+                    )
+                }
+
+                NegCloseCmd.LABEL -> {
+                    NegCloseCmd(
+                        subId = jp.nextTextValue(),
+                    )
+                }
+
                 else -> {
                     throw IllegalArgumentException("Message $type is not supported")
                 }

quartz/src/jvmAndroid/kotlin/com/vitorpamplona/quartz/nip01Core/relay/commands/toRelay/CommandSerializer.kt

@@ -25,6 +25,9 @@ import com.fasterxml.jackson.databind.SerializerProvider
 import com.fasterxml.jackson.databind.ser.std.StdSerializer
 import com.vitorpamplona.quartz.nip01Core.jackson.EventSerializer
 import com.vitorpamplona.quartz.nip01Core.relay.filters.FilterSerializer
+import com.vitorpamplona.quartz.nip77Negentropy.NegCloseCmd
+import com.vitorpamplona.quartz.nip77Negentropy.NegMsgCmd
+import com.vitorpamplona.quartz.nip77Negentropy.NegOpenCmd
 
 class CommandSerializer : StdSerializer<Command>(Command::class.java) {
     val eventSerializer = EventSerializer()
@@ -65,6 +68,21 @@ class CommandSerializer : StdSerializer<Command>(Command::class.java) {
                 }
             }
 
+            is NegOpenCmd -> {
+                gen.writeString(cmd.subId)
+                filterSerializer.serialize(cmd.filter, gen, provider)
+                gen.writeString(cmd.initialMessage)
+            }
+
+            is NegMsgCmd -> {
+                gen.writeString(cmd.subId)
+                gen.writeString(cmd.message)
+            }
+
+            is NegCloseCmd -> {
+                gen.writeString(cmd.subId)
+            }
+
             else -> {
                 null
             }