Harden e2e waits against loaded-box flakes; add AGENTS.md

tests/e2e/admin/index.py

@@ -1,5 +1,5 @@
 # retoor <retoor@molodetz.nl>
-from tests.conftest import login_admin
+from tests.conftest import goto_ready, login_admin
 
 ADMIN_PAGES = ["/admin", "/admin/posts", "/admin/joins", "/admin/services", "/admin/services/backup", "/admin/trash", "/admin/settings", "/admin/users", "/admin/audit", "/admin/backups", "/admin/stats", "/notifications", "/profile/api-key", "/docs/api/admin"]
 
@@ -7,8 +7,7 @@ ADMIN_PAGES = ["/admin", "/admin/posts", "/admin/joins", "/admin/services", "/ad
 def test_admin_pages_have_no_js_errors(page, app_server):
     login_admin(page, app_server)
     for path in ADMIN_PAGES:
-        page.goto(app_server + path, wait_until="domcontentloaded")
-        page.wait_for_selector("html[data-app=ready]")
+        goto_ready(page, app_server + path)
     page.goto(app_server + "/admin/services/backup", wait_until="domcontentloaded")
     page.click("[data-tab=logs]")
     assert page.locator("[data-panel=logs]").is_visible()