fix(artifacts): auto-capture leaves a web app's own HTML pages alone

At a session's Stop every untracked .html was snapshotted as a report, so a
web project not yet committed had its index.html taken into its owner's
Artifacts. An index.html, a page under a site folder (www, public, dist,
build, src, static, templates, assets, site, _site) or one beside scripts or
stylesheets (outside the workspace root) is now a site's own page and left
alone; a standalone HTML report is still captured.

server/__tests__/artifacts.test.js

@@ -981,6 +981,23 @@ describe("outputs captured at a session's stop", () => {
     );
     assert.deepEqual(await artifacts.captureOutputs("no-such-session"), []);
   });
+
+  it("leaves a web app's own pages alone and still takes a standalone HTML report", async () => {
+    const put = (rel, text = "<p>x</p>") => {
+      fs.mkdirSync(path.dirname(path.join(ws, rel)), { recursive: true });
+      fs.writeFileSync(path.join(ws, rel), text);
+      const soon = new Date(Date.now() + 5 * 60 * 1000);
+      fs.utimesSync(path.join(ws, rel), soon, soon);
+    };
+    put("app/index.html");
+    put("app/www/page.html");
+    put("widget/view.html");
+    put("widget/view.js", "x()");
+    put("summary-report.html");
+    put("out/q3.html");
+    const got = (await artifacts.captureOutputs("s1")).map((r) => r.source).sort();
+    assert.deepEqual(got, ["out/q3.html", "summary-report.html"]);
+  });
 });
 
 describe("unowned rows", () => {