Add license headers

Author: JasonHorkles

src/main/java/net/silverstonemc/expensivedeaths/DeathEvent.java

@@ -1,3 +1,5 @@
+// Copyright JasonHorkles and contributors
+// SPDX-License-Identifier: GPL-3.0-or-later
 package net.silverstonemc.expensivedeaths;
 
 import net.milkbowl.vault.economy.Economy;

src/main/java/net/silverstonemc/expensivedeaths/Execution.java

@@ -1,3 +1,5 @@
+// Copyright JasonHorkles and contributors
+// SPDX-License-Identifier: GPL-3.0-or-later
 package net.silverstonemc.expensivedeaths;
 
 import com.google.common.base.Suppliers;

src/main/java/net/silverstonemc/expensivedeaths/ExpensiveDeaths.java

@@ -1,3 +1,20 @@
+/*
+ * ExpensiveDeaths - a Minecraft plugin
+ * Copyright (C) 2026 JasonHorkles and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
 package net.silverstonemc.expensivedeaths;
 
 import net.milkbowl.vault.economy.Economy;

src/main/java/net/silverstonemc/expensivedeaths/RespawnEvent.java

@@ -1,3 +1,5 @@
+// Copyright JasonHorkles and contributors
+// SPDX-License-Identifier: GPL-3.0-or-later
 package net.silverstonemc.expensivedeaths;
 
 import org.bukkit.entity.Player;

src/main/java/net/silverstonemc/expensivedeaths/UpdateChecker.java

@@ -1,3 +1,5 @@
+// Copyright JasonHorkles and contributors
+// SPDX-License-Identifier: GPL-3.0-or-later
 package net.silverstonemc.expensivedeaths;
 
 import org.bukkit.ChatColor;