A shared party dialog objective is always complete

QuestDialog.isPartyCompleted's shared branch builds readValues by recording
only true: a dialog nobody has read is never put in the map at all. The check
underneath returns false only on finding a false, so it never can, and an
empty map returns true besides.

The result is that a party on a shared dialog objective has finished it before
anyone speaks to anybody, and a quest waiting on that objective can be handed
in immediately.

Every required dialog now starts unread, which is the line that was missing.
The loop below it was already right and had nothing to find.

Only the shared mode is affected. All and Leader iterate the dialogs directly
and return false on the first unread one.

src/main/java/noppes/npcs/quests/QuestDialog.java

@@ -264,6 +264,12 @@ public class QuestDialog extends QuestInterface implements IQuestDialog {
             return true;
         } else {
             HashMap<Integer, Boolean> readValues = new HashMap<>();
+            // Every required dialog starts unread. Without this the map only ever receives true,
+            // so the check below cannot find a false and a shared objective is always complete --
+            // including for a party that has read nothing at all.
+            for (int dialogId : dialogs.values()) {
+                readValues.put(dialogId, false);
+            }
             for (UUID uuid : party.getPlayerUUIDs()) {
                 EntityPlayer player = NoppesUtilServer.getPlayer(uuid);
                 PlayerData playerData;