:nut_and_bolt: A relentless key-value store for the browser.
Fixed: Cross-origin cookies are now stored with SameSite=None, Secure=true, as required. Other cookies remain set with SameSite=Lax and Secure=false -- the same defaults as if SameSite and Secure remained unset. Huge thank you to @zproxyz.
Fixed: Only add IndexedDbStore and LocalStorageStore if accessible.
Added: Cross-origin and same-origin tests.