现有组件功能与Amesim组件比较对齐，补全功能；仿真服务启动环境检测，旧版json工程文件适配读取

frontend/tests/e2e/project-initial-viewport.spec.ts

@@ -0,0 +1,72 @@
+import { test, expect } from "@playwright/test";
+import { prepareApp, wideProject } from "./fixtures";
+
+for (const action of ["import", "load", "recover"] as const) {
+  test(`${action}: first painted project is already fitted, including replacement with identical node IDs`, async ({ page }) => {
+    await prepareApp(page);
+    await page.goto("/");
+    await expect(page.getByRole("button", { name: /通用测试元件/ })).toBeVisible();
+    const old = { ...wideProject, nodes: wideProject.nodes.map((node, index) => ({
+      ...node, position: { x: index * 70, y: 0 },
+    })) };
+    if (action !== "recover") {
+      await page.locator('input[type="file"]').setInputFiles({ name: "old.json", mimeType: "application/json",
+        buffer: Buffer.from(JSON.stringify(old)) });
+      await expect(page.locator(".flow-canvas")).not.toHaveClass(/is-fitting-project/);
+    }
+    await page.evaluate(({ project, action }) => {
+      const key = action === "recover" ? "system-simulation-flow:autosave" : "system-simulation-flow:project:target";
+      localStorage.setItem(key, JSON.stringify(project));
+    }, { project: wideProject, action });
+    if (action === "recover") {
+      await page.reload();
+      await expect(page.getByRole("button", { name: "恢复草稿", exact: true })).toBeEnabled();
+    }
+    if (action === "load") await page.getByRole("textbox", { name: "工程", exact: true }).fill("target");
+
+    // Frame sampling, not just final bounds: detect even a single visible frame
+    // with the incoming wide graph rendered at the previous/default scale.
+    await page.evaluate(() => {
+      const samples: Array<{ opacity: number; fits: boolean; transform: string }> = [];
+      Object.assign(window, { projectPaintSamples: samples, projectPaintDone: false });
+      const sample = () => {
+        const canvas = document.querySelector<HTMLElement>(".flow-canvas")!;
+        const viewport = canvas.querySelector<HTMLElement>(".react-flow__viewport")!;
+        const nodes = [...canvas.querySelectorAll<HTMLElement>(".react-flow__node")];
+        // The last incoming node is positioned far away, unlike the old compact graph.
+        const incoming = nodes.find(node => node.dataset.id === "generic_sensor_4");
+        if (incoming && incoming.style.transform.includes("1860")) {
+          const bounds = canvas.getBoundingClientRect();
+          samples.push({ opacity: Number(getComputedStyle(viewport).opacity),
+            transform: getComputedStyle(viewport).transform,
+            fits: nodes.every(node => {
+              const rect = node.getBoundingClientRect();
+              return rect.left >= bounds.left - 1 && rect.right <= bounds.right + 1 &&
+                rect.top >= bounds.top - 1 && rect.bottom <= bounds.bottom + 1;
+            }),
+          });
+        }
+        if (!(window as unknown as { projectPaintDone: boolean }).projectPaintDone) requestAnimationFrame(sample);
+      };
+      requestAnimationFrame(sample);
+    });
+    if (action === "import") {
+      await page.locator('input[type="file"]').setInputFiles({ name: "target.json", mimeType: "application/json",
+        buffer: Buffer.from(JSON.stringify(wideProject)) });
+    } else {
+      await page.getByRole("button", { name: action === "load" ? "加载工程" : "恢复草稿", exact: true }).click();
+    }
+    await expect(page.locator(".flow-canvas")).not.toHaveClass(/is-fitting-project/);
+    const samples = await page.evaluate(async () => {
+      for (let frame = 0; frame < 12; frame++) await new Promise<void>(resolve => requestAnimationFrame(() => resolve()));
+      const state = window as unknown as { projectPaintDone: boolean;
+        projectPaintSamples: Array<{ opacity: number; fits: boolean; transform: string }> };
+      state.projectPaintDone = true;
+      return state.projectPaintSamples;
+    });
+    const visible = samples.filter(sample => sample.opacity > 0);
+    expect(visible.length).toBeGreaterThan(0);
+    expect(visible.every(sample => sample.fits), JSON.stringify(samples)).toBe(true);
+    expect(new Set(visible.map(sample => sample.transform)).size).toBe(1);
+  });
+}