fix(printers): post-#1661 cleanup — test fixtures + remove hover-card fly-in

- The Speed and AMS load/unload tests broke after the printer-card
        refactor in #1661 (icon-only Gauge button replaced the "100%" badge,
        hover-card actions replaced the kebab "Slot options" button). Add
        data-testid="speed-control" + data-testid="filament-slot" as stable
        test hooks, rewrite both files around them. Parametrize the four-mode
        speed-selection test. Update the "RUNNING hides menu" assertion to
        "Load/Unload buttons exist but are disabled" — the new UX shows
        actions on hover and disables them rather than hiding the trigger.
      - Drop `animate-in fade-in-0 zoom-in-95 duration-150` from
        FilamentHoverCard and EmptySlotHoverCard. The card briefly painted
        at the offscreen (-9999, -9999) coords during the zoom-in transition,
        reading as a fly-in from the upper-left corner. With the animation
        gone it just appears in place at its computed position.

frontend/src/components/FilamentHoverCard.tsx

@@ -192,7 +192,7 @@ export function FilamentHoverCard({ data, children, disabled, className = '', sp
       {isVisible && createPortal(
         <div
           ref={cardRef}
-          className="fixed z-[60] animate-in fade-in-0 zoom-in-95 duration-150"
+          className="fixed z-[60]"
           style={{
             top: coords?.top ?? -9999,
             left: coords?.left ?? -9999,
@@ -578,7 +578,7 @@ export function EmptySlotHoverCard({ children, className = '', configureSlot, on
       {isVisible && createPortal(
         <div
           ref={cardRef}
-          className="fixed z-[60] animate-in fade-in-0 zoom-in-95 duration-150"
+          className="fixed z-[60]"
           style={{
             top: coords?.top ?? -9999,
             left: coords?.left ?? -9999,