Expose server build information

Co-authored-by: Professor Bloodstone <git@bloodstone.dev>
Co-authored-by: Mark Vainomaa <mikroskeem@mikroskeem.eu>
Co-authored-by: masmc05 <masmc05@gmail.com>
Co-authored-by: Riley Park <rileysebastianpark@gmail.com>

paper-api/src/main/java/com/destroystokyo/paper/util/VersionFetcher.java

@@ -0,0 +1,47 @@
+package com.destroystokyo.paper.util;
+
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import org.bukkit.Bukkit;
+import org.jetbrains.annotations.ApiStatus;
+import org.jspecify.annotations.NullMarked;
+
+@NullMarked
+public interface VersionFetcher {
+
+    /**
+     * Amount of time to cache results for in milliseconds
+     * <p>
+     * Negative values will never cache.
+     *
+     * @return cache time
+     */
+    long getCacheTime();
+
+    /**
+     * Gets the version message to cache and show to command senders.
+     *
+     * <p>NOTE: This is run in a new thread separate from that of the command processing thread</p>
+     *
+     * @param serverVersion the current version of the server (will match {@link Bukkit#getVersion()})
+     * @return the message to show when requesting a version
+     */
+    Component getVersionMessage(String serverVersion);
+
+    @ApiStatus.Internal
+    class DummyVersionFetcher implements VersionFetcher {
+
+        @Override
+        public long getCacheTime() {
+            return -1;
+        }
+
+        @Override
+        public Component getVersionMessage(final String serverVersion) {
+            Bukkit.getLogger().warning("Version provider has not been set, cannot check for updates!");
+            Bukkit.getLogger().info("Override the default implementation of org.bukkit.UnsafeValues#getVersionFetcher()");
+            new Throwable().printStackTrace();
+            return Component.text("Unable to check for updates. No version provider set.", NamedTextColor.RED);
+        }
+    }
+}