While getting the editor e2e suite green, three "stale test" failures turned
out to be real bugs (per the reporter's hunch that tests might be catching
real issues):
- Layer effects (drop shadow, glows) never applied. The panel wrote effects
into `attrs.effects` through updateObject, but the panel and renderer both
read the object's top-level `effects`, so the toggle never persisted. Add a
dedicated `setObjectEffects` store action and route the panel through it.
- Object flip (transform tool) did nothing. No object renderer applied
`scaleX`/`scaleY`, and the flip negated scale without compensating position.
Apply scale in the renderers and flip in place: mirror points for stroke
objects, negate scale + shift position for sized objects.
(The paint-bucket / pixel-tool coordinate bug and the broken-at-non-100%-zoom
export were fixed in the preceding #259 change.)
Also adds a small "Beta" badge to the editor (welcome heading + nav link) and
repairs ~18 stale editor e2e specs whose selectors/assertions had drifted from
the current UI: the options bar is `h-9` not `h-10` (added a stable
`data-testid`), the menu bar is `h-8`/`bg-background`, the flip button
aria-labels are lowercase, the welcome "Image Editor" heading collides with an
sr-only `<h1>`, the color-picker tabs need a role-scoped selector, and the
magic-wand / flip tests now use deterministic setup and assert the actual
effect instead of fragile screenshot diffs.
SnapOtter