Makes sure quotes only happen once in events.

quartz/src/commonMain/kotlin/com/vitorpamplona/quartz/nip01Core/core/TagArrayBuilder.kt

@@ -72,6 +72,15 @@ class TagArrayBuilder<T : IEvent> {
         return this
     }
 
+    fun addUniqueValueIfNew(tag: Array<String>): TagArrayBuilder<T> {
+        if (tag.has(1) || tag[0].isEmpty() || tag[1].isEmpty()) return this
+        val list = tagList.getOrPut(tag[0], ::mutableListOf)
+        if (list.none { it.valueOrNull() == tag[1] }) {
+            list.add(tag)
+        }
+        return this
+    }
+
     fun addAll(tag: List<Array<String>>): TagArrayBuilder<T> {
         tag.forEach(::add)
         return this

quartz/src/commonMain/kotlin/com/vitorpamplona/quartz/nip18Reposts/quotes/TagArrayBuilderExt.kt

@@ -37,12 +37,12 @@ fun <T : Event> TagArrayBuilder<T>.quotes(tag: List<QTag>) = addAll(tag.map { it
 
 fun <T : Event> TagArrayBuilder<T>.quote(entity: Entity) =
     when (entity) {
-        is NNote -> add(entity.toQuoteTagArray())
-        is NEvent -> add(entity.toQuoteTagArray())
-        is NAddress -> add(entity.toQuoteTagArray())
-        is NEmbed -> add(entity.toQuoteTagArray())
-        is NPub -> add(entity.toQuoteTagArray())
-        is NProfile -> add(entity.toQuoteTagArray())
+        is NNote -> addUniqueValueIfNew(entity.toQuoteTagArray())
+        is NEvent -> addUniqueValueIfNew(entity.toQuoteTagArray())
+        is NAddress -> addUniqueValueIfNew(entity.toQuoteTagArray())
+        is NEmbed -> addUniqueValueIfNew(entity.toQuoteTagArray())
+        is NPub -> addUniqueValueIfNew(entity.toQuoteTagArray())
+        is NProfile -> addUniqueValueIfNew(entity.toQuoteTagArray())
         else -> this
     }