fix: smooth persona hover transitions

Preserve the original reflection material while adding pointer inertia and a short exit hold. Retain the Rive pointer constraint through the fade and blend rapid re-entry to avoid abrupt changes.

Cover timing, re-entry, cancellation, renderer disposal and native Rive frames. The fade regression fails with the previous resource and passes with the updated resource.

tests/browser/agent-orb.e2e.ts

@@ -121,7 +121,7 @@ test("renders original Obsidian, caches across reloads and releases offscreen re
   });
 });
 
-test("pointer coordinates reach the native hover listener in the launcher and header", async ({ page }) => {
+test("pointer coordinates reach the native hover listener in the launcher and header", async ({ page }, testInfo) => {
   await page.addInitScript(() => {
     const addListener = HTMLCanvasElement.prototype.addEventListener;
     HTMLCanvasElement.prototype.addEventListener = function (type, listener, options) {
@@ -144,7 +144,8 @@ test("pointer coordinates reach the native hover listener in the launcher and he
   await page.goto("/", { waitUntil: "domcontentloaded" });
   const launcher = page.getByLabel("Agent 折叠栏");
   const panel = page.getByRole("complementary", { name: "Agent 命令面板" });
-  for (const orb of [launcher.locator("[data-agent-orb]"), panel.locator("header [data-agent-orb]")]) {
+  const orbs = [launcher.locator("[data-agent-orb]"), panel.locator("header [data-agent-orb]")];
+  for (const [index, orb] of orbs.entries()) {
     await ready(orb);
     const bounds = (await orb.boundingBox())!;
     for (const x of [0.25, 0.75, 0.5]) {
@@ -154,6 +155,13 @@ test("pointer coordinates reach the native hover listener in the launcher and he
         return point ? JSON.parse(point) : null;
       }).toEqual({ x, y: 0.5 });
     }
+    await testInfo.attach(`original-hover-${index === 0 ? "launcher" : "header"}`, {
+      body: await page.screenshot({
+        path: `/tmp/nexttjwater-persona-hover-${index}.png`,
+        clip: { x: Math.max(0, bounds.x - 12), y: Math.max(0, bounds.y - 12), width: 240, height: 104 }
+      }),
+      contentType: "image/png"
+    });
     await page.mouse.move(600, 600);
     await expect(orb).toHaveAttribute("data-hovered", "false");
     if (!(await panel.isVisible())) await launcher.getByRole("button").click();