fix(projects+assets): 项目封面引用真实商品图 + 资产库排除软删资产

- 项目卡封面:废弃「项目名关键词→静态 mock 假图」映射(与真实数据脱节,导致全是假面膜图),
  改用后端 cover_preview_url(取商品 cover_asset 主图);无商品图 → 干净占位
- 资产库 queryset/summary/facets 补 is_deleted=False:软删资产不再出现在资产库与 tab 计数
  (此前 is_deleted 字段在资产库未生效,软删无效)
- 单测 AssetSoftDeleteTests:列表 + 计数均排除软删

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

core/qa/visual-parity/_cleanup-verify.mjs

@@ -0,0 +1,27 @@
+import { chromium } from "playwright";
+import fs from "node:fs";
+import path from "node:path";
+const BASE = process.env.BASE || "http://localhost:5200";
+const OUT = path.resolve("../../../_qa_shots/cleanup");
+fs.mkdirSync(OUT, { recursive: true });
+const browser = await chromium.launch({ headless: true });
+const r = { consoleErrors: [] };
+const ctx = await browser.newContext({ viewport: { width: 1440, height: 900 } });
+const p = await ctx.newPage();
+p.on("console", (m) => { if (m.type() === "error") r.consoleErrors.push(m.text()); });
+p.on("pageerror", (e) => r.consoleErrors.push("PAGEERR:" + e.message));
+await p.goto(BASE + "/login", { waitUntil: "load" });
+await p.waitForTimeout(400);
+await p.fill("#auth-username", "airshelf"); await p.fill("#auth-pwd", "Restraint2026");
+await p.click("button.btn-cta");
+await p.waitForFunction(() => !location.pathname.startsWith("/login"), { timeout: 12000 });
+await p.goto(BASE + "/projects", { waitUntil: "load" }); await p.waitForTimeout(2600);
+await p.screenshot({ path: path.join(OUT, "projects.png"), fullPage: true });
+await p.goto(BASE + "/library", { waitUntil: "load" }); await p.waitForTimeout(2600);
+r.libTabs = (await p.locator(".tab").allInnerTexts().catch(() => [])).join(" | ");
+await p.screenshot({ path: path.join(OUT, "library.png"), fullPage: true });
+await p.goto(BASE + "/models", { waitUntil: "load" }); await p.waitForTimeout(2600);
+r.modelCards = await p.locator(".model-card").count();
+await p.screenshot({ path: path.join(OUT, "models.png"), fullPage: true });
+await browser.close();
+console.log(JSON.stringify(r, null, 2));