Drop manual isEditable copy in CraftSign

Signs no longer have a specific isEdiable state, the entire API in this
regard needs updating/deprecation. The boolean field is completely gone,
replaced by a uuid (which will need a new setEditingPlayer(UUID) method
on the Sign interface), and the current upstream implementation of
setEdiable simply flips the is_waxed state.

This patch is hence not needed as it neither allows editing (which will
be redone in a later patch) nor is required to copy the is_waxed boolean
flag as it lives in the signs compound tag and is covered by applyTo.

patches/server/0925-Win-Screen-API.patch

@@ -0,0 +1,38 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Lama06 <andreasprues36@gmail.com>
+Date: Sat, 21 Jan 2023 13:53:23 +0100
+Subject: [PATCH] Win Screen API
+
+== AT ==
+public net.minecraft.server.level.ServerPlayer seenCredits
+
+diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
+index edb5777a6b69d2947708d6799f0054b438078628..fc71dfcf4387c355a69a8bbfaec17aafb6d98d2d 100644
+--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
++++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
+@@ -1203,6 +1203,25 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
+         this.getHandle().connection.send(packet);
+     }
+ 
++    // Paper start
++    @Override
++    public void showWinScreen() {
++        if (getHandle().connection == null) return;
++        var packet = new ClientboundGameEventPacket(ClientboundGameEventPacket.WIN_GAME, 1);
++        getHandle().connection.send(packet);
++    }
++
++    @Override
++    public boolean hasSeenWinScreen() {
++        return getHandle().seenCredits;
++    }
++
++    @Override
++    public void setHasSeenWinScreen(boolean hasSeenWinScreen) {
++        getHandle().seenCredits = hasSeenWinScreen;
++    }
++    // Paper end
++
+     @Override
+     public void setRotation(float yaw, float pitch) {
+         // Paper start - Teleport API