加一套抓真实请求做预设对比的工具，并把三份预设的机制差异记进 README。

tools/st-request-diff/peek-entry.mjs

@@ -0,0 +1,12 @@
+// 看预设里某条目的正文开头与宏统计。用法: node peek-entry.mjs <preset.json> <identifier> [字数]
+import { readFileSync } from "node:fs";
+const [file, id, n] = process.argv.slice(2);
+const raw = JSON.parse(readFileSync(file, "utf8"));
+const p = (raw.prompts || []).find((x) => x.identifier === id);
+if (!p) { console.log("没有这个 identifier: " + id); process.exit(1); }
+const text = p.content || "";
+console.log("name=" + p.name + " role=" + p.role + " 字数=" + text.length);
+const macros = text.match(/\{\{[^}]*\}\}/g) || [];
+console.log("宏 " + macros.length + " 个: " + macros.slice(0, 12).join(" "));
+console.log("开头: " + text.slice(0, Number(n || 300)));
+console.log("结尾: " + text.slice(-200));