Offer background effects as a grid in the camera menu

- The camera menu's blur toggle becomes a Background effects section
  under the cameras: no effect, blur and the two shipped backgrounds as
  one radio choice of tiles, three across. It scrolls with the device
  list, so it stays reachable in a short call, and choosing keeps the
  menu open. The lobby gets it too, as both render the same footer.
- The footer's view model gives the options, the notice and the actions;
  the footer only names them.
- Each tile is Compound's MenuItem as a menuitemradio, styled as a tile.
  Compound makes it an item of the dropdown, so the arrow keys walk the
  tiles with the device rows, and takes its tap in the phone drawer. A
  tile that can't be chosen has no select handler, so the keyboard passes
  over it.
- Where the browser can't run effects the tiles are shown, disabled and
  explained by a notice the group is described by. No effect stays
  choosable and shows as in force. The notice is in the scrolling list,
  so a short call doesn't push the menu out of it.
- Section headings are raised, or the positioned tiles scroll over the
  one they sit under; raised within the list only, so the menu's frame
  stays over them. Tiles clip with overflow: clip; with hidden they are
  scroll containers, which focus scrolls into view without their border.
- End to end on Chromium and Firefox: a shipped background chosen in the
  lobby shows in the preview, and None after Blur draws nothing, counted
  in WebGL draws (Blur: about 1400 a second on Chromium, 2300 on
  Firefox).
- The Quick Audio Menu's test of the camera menu keeps its name and now
  finds blur among the effects rather than as a toggle.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/components/CallFooter.tsx

@@ -7,6 +7,7 @@ Please see LICENSE in the repository root for full details.
 
 import { type FC, type JSX, type Ref, useMemo } from "react";
 import classNames from "classnames";
+import { useTranslation } from "react-i18next";
 
 import LogoMark from "../icons/LogoMark.svg?react";
 import LogoType from "../icons/LogoType.svg?react";
@@ -31,6 +32,15 @@ import { type ViewModel } from "../state/ViewModel";
 import { useBehavior } from "../useBehavior";
 import { type LayoutSwitchViewModel } from "../state/LayoutSwitchViewModel";
 import { LayoutSwitch } from "../room/LayoutSwitch";
+import { type BackgroundEffectOption } from "./BackgroundEffectGrid";
+
+/** A background effect on offer, which the view names. */
+export interface BackgroundEffectChoice {
+  /** Its option id, as `backgroundEffect` gives the one in force. */
+  id: string;
+  kind: "none" | "blur" | "image";
+  imageUrl?: string;
+}
 
 export interface AudioOutputSwitcher {
   targetOutput: string;
@@ -56,20 +66,27 @@ export interface FooterActions {
   toggleAudio: (() => void) | undefined;
   /** Also controls if the videoMute button is disabled */
   toggleVideo: (() => void) | undefined;
-  toggleBlur: (() => void) | undefined;
+  /** Undefined where background effects can't be chosen. */
+  selectBackgroundEffect: ((id: string) => void) | undefined;
   toggleScreenSharing: (() => void) | undefined;
   /** Also controls if the settings button is visible */
   openSettings: (() => void) | undefined;
   /** Also controls if the hangup button is visible */
   hangup: (() => void) | undefined;
 }
+
 // we do not use any ? optional properties so that the vm type is including all fields.
 export interface FooterState {
   audioEnabled: boolean;
   audioBusy: boolean;
   videoEnabled: boolean;
   videoBusy: boolean;
-  videoBlurEnabled: boolean;
+  /** The background effect in force, as its option id. */
+  backgroundEffect: string;
+  /** Every effect on offer, in the order they are shown. */
+  backgroundEffects: BackgroundEffectChoice[];
+  /** What the user is told about effects here, if anything. */
+  backgroundEffectNotice: "unavailable" | undefined;
   showFooter: boolean;
 
   /* This is needed for WindowMode = "flat" */
@@ -117,12 +134,14 @@ export interface FooterProps {
   children?: JSX.Element | JSX.Element[] | false;
   vm: ViewModel<FooterSnapshot>;
 }
+
 export const CallFooter: FC<FooterProps> = ({
   className,
   ref,
   children,
   vm,
 }) => {
+  const { t } = useTranslation();
   const asOverlay = useBehavior(vm.asOverlay$);
   const showFooter = useBehavior(vm.showFooter$);
   const hideControls = useBehavior(vm.hideControls$);
@@ -151,8 +170,12 @@ export const CallFooter: FC<FooterProps> = ({
   const selectedAudioOutput = useBehavior(vm.selectedAudioOutput$);
   const selectAudioOutputOption = useBehavior(vm.selectAudioOutputOption$);
   const selectVideoButtonOption = useBehavior(vm.selectVideoButtonOption$);
-  const toggleBlur = useBehavior(vm.toggleBlur$);
-  const videoBlurEnabled = useBehavior(vm.videoBlurEnabled$);
+  const backgroundEffect = useBehavior(vm.backgroundEffect$);
+  const selectBackgroundEffect = useBehavior(vm.selectBackgroundEffect$);
+  const backgroundEffectNotice = useBehavior(vm.backgroundEffectNotice$);
+  const backgroundEffects = useBackgroundEffectLabels(
+    useBehavior(vm.backgroundEffects$),
+  );
   const buttonSize = useBehavior(vm.buttonSize$);
   const showLogo = useBehavior(vm.showLogo$);
 
@@ -214,8 +237,14 @@ export const CallFooter: FC<FooterProps> = ({
         options={videoOptions}
         selectedOption={selectedVideo}
         onSelect={selectVideoButtonOption}
-        videoBlurToggleClick={toggleBlur}
-        videoBlurEnabled={videoBlurEnabled}
+        backgroundEffects={backgroundEffects}
+        selectedBackgroundEffect={backgroundEffect}
+        onSelectBackgroundEffect={selectBackgroundEffect}
+        backgroundEffectNotice={
+          backgroundEffectNotice === "unavailable"
+            ? t("background_effects.unavailable")
+            : undefined
+        }
       />,
     );
   } else {
@@ -340,3 +369,21 @@ const TilesDebugInfo: FC<TilesDebugInfoProps> = ({ generation$ }) => {
   const generation = useBehavior(generation$);
   return `Tiles generation: ${generation}`;
 };
+
+function useBackgroundEffectLabels(
+  choices: BackgroundEffectChoice[],
+): BackgroundEffectOption[] {
+  const { t } = useTranslation();
+  return useMemo(() => {
+    let pictures = 0;
+    return choices.map((choice) => ({
+      ...choice,
+      label:
+        choice.kind === "none"
+          ? t("background_effects.none")
+          : choice.kind === "blur"
+            ? t("background_effects.blur")
+            : t("background_effects.numbered", { n: ++pictures }),
+    }));
+  }, [choices, t]);
+}