Add the chat log store missing from earlier commits

TeamspeakConnection and ChatPanel already use com.ts3client.chatlog, but the
package itself was never committed, so the tree did not build.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

ts3-client/core/src/test/java/com/ts3client/chatlog/ChatLogStoreTest.java

@@ -0,0 +1,43 @@
+package com.ts3client.chatlog;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class ChatLogStoreTest {
+
+    @TempDir
+    Path temp;
+
+    @Test
+    void writesTs3CompatibleClientLogNamesAndEntries() throws Exception {
+        ChatLogStore logs = new ChatLogStore(temp, "+Tyg2JtxE8vRNZp+JiUBnmBh0MY=");
+
+        logs.begin();
+        logs.appendPrivateMessage("cckqISCrfr6Lq2SLMC//afsbO9w=", true,
+                610, "bdrlePoB9hU8K8CyjCabY07t3Wo=", "ericek111", "hello");
+
+        Path serverDir = temp.resolve("K1R5ZzJKdHhFOHZSTlpwK0ppVUJubUJoME1ZPQ==");
+        Path clientHtml = serverDir.resolve("clients")
+                .resolve("Y2NrcUlTQ3JmcjZMcTJTTE1DLy9hZnNiTzl3PQ==.html");
+        Path clientTxt = serverDir.resolve("clients")
+                .resolve("Y2NrcUlTQ3JmcjZMcTJTTE1DLy9hZnNiTzl3PQ==.txt");
+
+        assertTrue(Files.isRegularFile(serverDir.resolve("server.html")));
+        assertTrue(Files.isRegularFile(serverDir.resolve("channel.html")));
+        assertTrue(Files.isRegularFile(clientHtml));
+        assertEquals(1, Files.readAllLines(clientTxt).size());
+
+        List<String> history = logs.privateHtmlHistory("cckqISCrfr6Lq2SLMC//afsbO9w=");
+        assertEquals(1, history.size());
+        assertTrue(history.get(0).contains("TextMessage_Message"));
+        assertTrue(history.get(0).contains("ericek111"));
+        assertTrue(history.get(0).contains("hello"));
+    }
+}