feat(ast): 重构AST转储功能并添加tree_dump依赖

- 添加tree_dump库作为依赖项到ast模块
- 将ast_dump.h中的转储上下文结构替换为tree_dump.h中的统一实现
- 更新scc_ast_block_item_vec_t类型定义，支持stmt或decl的泛型指针
- 移除ast_dump.c中重复的缩进和上下文管理代码，使用tree_dump提供的功能
- 修改dump函数参数类型从scc_ast_dump_ctx_t为scc_tree_dump_ctx_t
- 在libs目录下新增tree_dump库，包含完整的树形结构转储功能

libs/tree_dump/include/tree_dump.h

@@ -0,0 +1,91 @@
+#ifndef __SCC_TREE_DUMP_H__
+#define __SCC_TREE_DUMP_H__
+
+#include <scc_core.h>
+
+#define SCC_TREE_DUMP_VERTICAL "| "
+#define SCC_TREE_DUMP_BRANCH "|-"
+#define SCC_TREE_DUMP_LAST_BRANCH "`-"
+#define SCC_TREE_DUMP_SPACE "  "
+
+#define SCC_TREE_DUMP_NODE_COLOR ANSI_FG_BLUE
+#define SCC_TREE_DUMP_VALUE_COLOR ANSI_FG_GREEN
+#define SCC_TREE_DUMP_BRANCH_COLOR ANSI_FG_YELLOW
+#define SCC_TREE_DUMP_RESET_COLOR ANSI_NONE
+
+// #define ANSI_FMT
+
+typedef SCC_VEC(cbool) scc_ast_dump_stack_t;
+
+typedef struct {
+    scc_ast_dump_stack_t stack; ///< 每层是否为最后子节点
+    cbool use_color;            ///< 是否使用颜色输出
+
+    const char *vertical;
+    const char *branch;
+    const char *last_branch;
+    const char *space;
+
+    const char *node_color;   ///< 节点类型颜色
+    const char *value_color;  ///< 值颜色
+    const char *branch_color; ///< 分支符号颜色
+    const char *reset_color;  ///< 重置颜色
+} scc_tree_dump_ctx_t;
+
+static inline void scc_tree_dump_ctx_init(scc_tree_dump_ctx_t *ctx,
+                                          cbool use_color) {
+    ctx->use_color = use_color;
+    scc_vec_init(ctx->stack);
+
+    ctx->vertical = SCC_TREE_DUMP_VERTICAL;
+    ctx->branch = SCC_TREE_DUMP_BRANCH;
+    ctx->last_branch = SCC_TREE_DUMP_LAST_BRANCH;
+    ctx->space = SCC_TREE_DUMP_SPACE;
+
+    ctx->node_color = use_color ? SCC_TREE_DUMP_NODE_COLOR : "";
+    ctx->value_color = use_color ? SCC_TREE_DUMP_VALUE_COLOR : "";
+    ctx->branch_color = use_color ? SCC_TREE_DUMP_BRANCH_COLOR : "";
+    ctx->reset_color = use_color ? SCC_TREE_DUMP_RESET_COLOR : "";
+}
+
+static inline void scc_tree_dump_ctx_drop(scc_tree_dump_ctx_t *ctx) {
+    scc_vec_free(ctx->stack);
+}
+
+// 打印缩进
+static void scc_tree_print_indent(scc_tree_dump_ctx_t *ctx) {
+    scc_vec_foreach(ctx->stack, i) {
+        cbool last_child = scc_vec_at(ctx->stack, i);
+        const char *data = null;
+        if (i + 1 == scc_vec_size(ctx->stack)) {
+            // 最后一层打印分支符号
+            data = last_child ? ctx->last_branch : ctx->branch;
+        } else {
+            data = last_child ? ctx->space : ctx->vertical;
+        }
+        Assert(data != null);
+        if (ctx->use_color) {
+            scc_printf("%s%s%s", ctx->branch_color, data, ctx->reset_color);
+        } else {
+            scc_printf("%s", data);
+        }
+    }
+}
+
+// 推入新的层级到栈中
+static inline void scc_tree_dump_push_level(scc_tree_dump_ctx_t *ctx,
+                                            cbool is_last_child) {
+    scc_vec_push(ctx->stack, is_last_child);
+}
+
+// 弹出当前层级
+static inline void scc_tree_dump_pop_level(scc_tree_dump_ctx_t *ctx) {
+    scc_vec_pop(ctx->stack);
+}
+
+// 获取当前层级深度
+static inline usize scc_tree_dump_depth(scc_tree_dump_ctx_t *ctx) {
+    return scc_vec_size(ctx->stack);
+}
+
+#endif /* __SCC_TREE_DUMP_H__ */