feat: support SVN auth and project credentials

- add username/password fields to project dialog and model
- pass optional auth to SVN info/status/log/diff/update/commit services
- centralize SVN CLI auth flags in SvnService and fix header text

Co-authored-by: Cursor <cursoragent@cursor.com>

src/main/java/com/svnmanager/service/DiffService.java

@@ -25,7 +25,7 @@ public class DiffService extends SvnService {
      * @throws InterruptedException 中断异常
      * @throws TimeoutException 超时异常
      */
-    public String getDiff(String workingDirectory, String filePath) 
+    public String getDiff(String workingDirectory, String filePath, String username, String password) 
             throws IOException, InterruptedException, TimeoutException {
         logger.debug("获取差异: {}", workingDirectory);
         
@@ -34,6 +34,7 @@ public class DiffService extends SvnService {
         }
         
         List<String> args = new ArrayList<>();
+        addAuthArgs(args, username, password);
         if (filePath != null && !filePath.isEmpty()) {
             args.add(filePath);
         }
@@ -57,8 +58,23 @@ public class DiffService extends SvnService {
      * @throws InterruptedException 中断异常
      * @throws TimeoutException 超时异常
      */
-    public String getDiff(String workingDirectory) 
+    public String getDiff(String workingDirectory)
             throws IOException, InterruptedException, TimeoutException {
-        return getDiff(workingDirectory, null);
+        return getDiff(workingDirectory, null, null, null);
+    }
+
+    /**
+     * 获取指定文件的差异（不带认证信息）
+     *
+     * @param workingDirectory 工作目录
+     * @param filePath 文件路径（null表示所有文件）
+     * @return 差异内容
+     * @throws IOException IO异常
+     * @throws InterruptedException 中断异常
+     * @throws TimeoutException 超时异常
+     */
+    public String getDiff(String workingDirectory, String filePath)
+            throws IOException, InterruptedException, TimeoutException {
+        return getDiff(workingDirectory, filePath, null, null);
     }
 }