Promotes Translate from an inline button under the input pane to
the primary 56x56 FAB at the bottom-right corner. Camera FAB
becomes the secondary in the stack, just above. Both share a
single .fab base class; positioning via .fab-primary /
.fab-secondary.
- Translate icon: Material Symbols `translate` (28 px).
- Pulsing-ring `busy` animation while a translation runs, since
the icon-only button can't show "Translating…" text anymore.
- body padding-bottom bumped to ~9 rem so the output pane
scrolls clear of the stacked FABs.
- ⌘/Ctrl-Enter still triggers translate via the existing
CodeMirror keymap; tooltip text updated.
f160c0510b