feat: contain mobile Device Setup focus (Closes #1134)

tests/e2e/test_mobile_home_bootstrap_release.py

@@ -148,12 +148,24 @@ def test_release_artifact_bootstraps_mobile_home_and_returns_from_insights(
             expect(page.locator("#device-setup-sheet")).to_be_visible()
             expect(page.locator("#device-storage-heading")).to_have_text("Private device storage")
             expect(page.locator("#device-storage-detail")).to_contain_text("private work records")
+            expect(page.locator("body > header")).to_have_attribute("inert", "")
+            expect(page.locator("main")).to_have_attribute("inert", "")
+            expect(dock).to_have_attribute("inert", "")
+            expect(page.locator("#close-device-setup")).to_be_focused()
+            page.keyboard.press("Shift+Tab")
+            expect(page.locator("#clear-private-device-data")).to_be_focused()
+            page.keyboard.press("Tab")
+            expect(page.locator("#close-device-setup")).to_be_focused()
             for selector in ("#clear-device-caches", "#clear-private-device-data"):
                 bounds = page.locator(selector).bounding_box()
                 assert bounds and bounds["height"] >= 44
             assert page.evaluate("document.documentElement.scrollWidth <= window.innerWidth")
-            page.locator("#close-device-setup").click()
+            page.go_back()
             expect(page.locator("#device-setup-sheet")).to_be_hidden()
+            expect(page.locator("#open-device-setup")).to_be_focused()
+            expect(page.locator("body > header")).not_to_have_attribute("inert", "")
+            expect(page.locator("main")).not_to_have_attribute("inert", "")
+            expect(dock).not_to_have_attribute("inert", "")
 
             page.locator("#active-devices").click()
             expect(page.locator("#active-devices-sheet")).to_be_visible()