feat: Phase1 项目骨架 - Maven项目结构、核心AgentLoop、6个工具、命令系统、控制台渲染、REPL会话

实现内容:
- pom.xml: JDK25 + Spring AI 2.0.0-M4 + JLine3 + Picocli
- core/AgentLoop: 基于ChatModel的显式工具循环（非ChatClient）
- tool/: Tool接口 + ToolRegistry + ToolCallbackAdapter（适配Spring AI）
- tool/impl/: BashTool, FileReadTool, FileWriteTool, FileEditTool, GlobTool, GrepTool
- command/: SlashCommand接口 + CommandRegistry + /help, /clear, /exit
- console/: AnsiStyle, BannerPrinter, ToolStatusRenderer, ThinkingRenderer, SpinnerAnimation, MarkdownRenderer
- context/: SystemPromptBuilder, ClaudeMdLoader（多级CLAUDE.md加载）
- repl/ReplSession: REPL主循环（Scanner降级方案）
- config/AppConfig: Spring Bean装配
- application.yml: Anthropic/OpenAI双模型配置

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

src/main/java/com/claudecode/console/SpinnerAnimation.java

@@ -0,0 +1,72 @@
+package com.claudecode.console;
+
+import java.io.PrintStream;
+
+/**
+ * 加载动画（Spinner）—— 对应 claude-code/src/components/Spinner.tsx。
+ * <p>
+ * 在等待 AI 响应时显示旋转动画。
+ */
+public class SpinnerAnimation {
+
+    private static final String[] FRAMES = {"⠋", "⠙", "⠹", "⠸", "⠼", "⠴", "⠦", "⠧", "⠇", "⠏"};
+    private static final int INTERVAL_MS = 80;
+
+    private final PrintStream out;
+    private volatile boolean running;
+    private Thread thread;
+    private String message = "Thinking";
+
+    public SpinnerAnimation(PrintStream out) {
+        this.out = out;
+    }
+
+    /** 启动 spinner */
+    public void start(String message) {
+        if (running) return;
+        this.message = message;
+        this.running = true;
+
+        thread = Thread.ofVirtual().name("spinner").start(() -> {
+            int idx = 0;
+            while (running) {
+                out.print(AnsiStyle.clearLine());
+                out.print(AnsiStyle.CYAN + "  " + FRAMES[idx % FRAMES.length]
+                        + " " + AnsiStyle.RESET + AnsiStyle.dim(this.message));
+                out.flush();
+                idx++;
+                try {
+                    Thread.sleep(INTERVAL_MS);
+                } catch (InterruptedException e) {
+                    Thread.currentThread().interrupt();
+                    break;
+                }
+            }
+            // 清除 spinner 行
+            out.print(AnsiStyle.clearLine());
+            out.flush();
+        });
+    }
+
+    /** 停止 spinner */
+    public void stop() {
+        running = false;
+        if (thread != null) {
+            thread.interrupt();
+            try {
+                thread.join(200);
+            } catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
+            }
+        }
+    }
+
+    /** 更新消息 */
+    public void updateMessage(String newMessage) {
+        this.message = newMessage;
+    }
+
+    public boolean isRunning() {
+        return running;
+    }
+}