feat(call): in-call soundboard, quality controls, room call-permissions

Element Call is now consumed as our self-built fork
(@lotusguild/element-call-embedded); wire up its previously-dormant
capabilities and document the fork as live.

Soundboard (P5-15): a call-bar button plays user-uploaded audio clips into the
call as a real published track (io.lotus.inject_audio) plus local playback.
Clips are uploadable like emoji/sticker packs, stored in io.lotus.soundboard
account data (synced across devices). Gated by a Settings toggle + volume.

Quality controls (P5-31): per-user mic/screenshare bitrate + screenshare
framerate (Settings -> Calls), applied via io.lotus.set_quality clamped to any
room cap. Room admins set caps and hard call-permissions (allow_screenshare /
allow_camera) in Room Settings -> Voice; the call bar hides blocked buttons.

- New: CallSoundboard, useSoundboard, soundboardClips; RoomQuality,
  useCallQuality, callQuality (+ unit tests).
- Optimistic-write RoomQuality admin UI (no stale-state clobber).
- Docs: mark EC fork live across README/FEATURES/TODO/BUGS/TESTING; add D2
  manual-test steps.

Numeric quality caps are client-cooperative; screenshare/camera permissions are
hard-enforced server-side (see LotusGuild/matrix voice-limit-guard).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/features/call/CallControls.tsx

@@ -37,6 +37,10 @@ import { stopPropagation } from '../../utils/keyboard';
 import { AsyncStatus, useAsyncCallback } from '../../hooks/useAsyncCallback';
 import { useCallEmbedRef } from '../../hooks/useCallEmbed';
 import { useAfkAutoMute } from '../../hooks/useAfkAutoMute';
+import { CallSoundboard } from './CallSoundboard';
+import { useStateEvent } from '../../hooks/useStateEvent';
+import { StateEvent } from '../../../types/matrix/room';
+import { RoomQualityContent } from '../../utils/callQuality';
 
 type CallControlsProps = {
   callEmbed: CallEmbed;
@@ -88,6 +92,19 @@ export function CallControls({ callEmbed }: CallControlsProps) {
   const [pttMode] = useSetting(settingsAtom, 'pttMode');
   const [pttKey] = useSetting(settingsAtom, 'pttKey');
   const [deafenKey] = useSetting(settingsAtom, 'deafenKey');
+  const [soundboardEnabled] = useSetting(settingsAtom, 'soundboardEnabled');
+
+  // [P5-31] Hard room publish policy — hide controls the server will refuse so
+  // users don't click dead buttons. Absent/true = allowed.
+  const roomQualityEvent = useStateEvent(callEmbed.room, StateEvent.LotusRoomQuality);
+  const roomQuality = roomQualityEvent?.getContent<RoomQualityContent>();
+  const cameraAllowed = roomQuality?.allow_camera !== false;
+  const screenshareAllowed = roomQuality?.allow_screenshare !== false;
+  // Keep a forbidden control visible while its track is still live (so the user
+  // can stop it); otherwise hide it entirely.
+  const showCamera = cameraAllowed || video;
+  const showScreenshare = screenshareAllowed || screenshare;
+  const showVideoGroup = showCamera || showScreenshare || !!document.fullscreenEnabled;
   const [pttActive, setPttActive] = useState(false);
 
   // Track microphone via ref so the PTT effect doesn't need it as a dep (avoids listener churn)
@@ -339,24 +356,31 @@ export function CallControls({ callEmbed }: CallControlsProps) {
               onToggle={() => callEmbed.control.toggleScreenshareAudio()}
             />
           </Box>
-          {!compact && <ControlDivider />}
-          <Box shrink="No" alignItems="Inherit" justifyContent="Inherit" gap="200">
-            <VideoButton enabled={video} onToggle={handleVideoToggle} />
-            <ScreenShareButton
-              enabled={screenshare}
-              onToggle={() =>
-                screenshare ? callEmbed.control.toggleScreenshare() : setShareConfirm(true)
-              }
-            />
-            {!!document.fullscreenEnabled && (
-              <FullscreenButton isFullscreen={isFullscreen} onToggle={handleFullscreen} />
-            )}
-          </Box>
+          {!compact && showVideoGroup && <ControlDivider />}
+          {showVideoGroup && (
+            <Box shrink="No" alignItems="Inherit" justifyContent="Inherit" gap="200">
+              {/* Show a forbidden control while its track is still live so the
+                  user can stop it; once stopped it hides and can't be restarted. */}
+              {showCamera && <VideoButton enabled={video} onToggle={handleVideoToggle} />}
+              {showScreenshare && (
+                <ScreenShareButton
+                  enabled={screenshare}
+                  onToggle={() =>
+                    screenshare ? callEmbed.control.toggleScreenshare() : setShareConfirm(true)
+                  }
+                />
+              )}
+              {!!document.fullscreenEnabled && (
+                <FullscreenButton isFullscreen={isFullscreen} onToggle={handleFullscreen} />
+              )}
+            </Box>
+          )}
         </Box>
         {!compact && <ControlDivider />}
         <Box alignItems="Center" gap="Inherit" grow="Yes" direction={compact ? 'Column' : 'Row'}>
           <Box shrink="No" alignItems="Inherit" justifyContent="Inherit" gap="200">
             <ChatButton />
+            {soundboardEnabled && <CallSoundboard callEmbed={callEmbed} />}
             <PopOut
               anchor={cords}
               position="Top"

src/app/features/call/CallSoundboard.tsx

@@ -0,0 +1,220 @@
+import React, { MouseEventHandler, useCallback, useRef, useState } from 'react';
+import {
+  Box,
+  Chip,
+  Icon,
+  IconButton,
+  Icons,
+  Menu,
+  PopOut,
+  RectCords,
+  Spinner,
+  Text,
+  Tooltip,
+  TooltipProvider,
+  color,
+  config,
+} from 'folds';
+import FocusTrap from 'focus-trap-react';
+import { CallEmbed } from '../../plugins/call';
+import { useMatrixClient } from '../../hooks/useMatrixClient';
+import { useSoundboard } from '../../hooks/useSoundboard';
+import { useSetting } from '../../state/hooks/settings';
+import { settingsAtom } from '../../state/settings';
+import { stopPropagation } from '../../utils/keyboard';
+import {
+  SOUNDBOARD_ACCEPT,
+  SOUNDBOARD_MAX_CLIPS,
+  playClipLocally,
+  resolveClipObjectUrl,
+} from '../../utils/soundboardClips';
+
+type CallSoundboardProps = {
+  callEmbed: CallEmbed;
+};
+
+/**
+ * [P5-15] In-call soundboard: trigger user-uploaded clips into the call. Each
+ * clip is published to peers as a separate track by the EC fork
+ * (`io.lotus.inject_audio`) and also played locally for the presser's feedback.
+ * Clips are uploadable/managed here and synced across devices via the
+ * `io.lotus.soundboard` account data (like custom emoji/sticker packs).
+ */
+export function CallSoundboard({ callEmbed }: CallSoundboardProps) {
+  const mx = useMatrixClient();
+  const { clips, addClip, removeClip } = useSoundboard();
+  const [soundboardVolume] = useSetting(settingsAtom, 'soundboardVolume');
+
+  const [cords, setCords] = useState<RectCords>();
+  const [busyId, setBusyId] = useState<string>();
+  const [uploading, setUploading] = useState(false);
+  const [error, setError] = useState<string>();
+  const fileInputRef = useRef<HTMLInputElement>(null);
+
+  const volume = Math.max(0, Math.min(1, soundboardVolume / 100));
+
+  const handleOpen: MouseEventHandler<HTMLButtonElement> = (evt) => {
+    setError(undefined);
+    setCords(evt.currentTarget.getBoundingClientRect());
+  };
+
+  const handlePlay = useCallback(
+    async (id: string, mxc: string) => {
+      setBusyId(id);
+      setError(undefined);
+      try {
+        const objectUrl = await resolveClipObjectUrl(mx, mxc);
+        callEmbed.control.injectAudio(objectUrl, volume);
+        playClipLocally(objectUrl, volume);
+      } catch {
+        setError('Could not play that clip.');
+      } finally {
+        setBusyId(undefined);
+      }
+    },
+    [mx, callEmbed, volume],
+  );
+
+  const handleFile = useCallback(
+    async (file: File | undefined) => {
+      if (!file) return;
+      setUploading(true);
+      setError(undefined);
+      try {
+        await addClip(file);
+      } catch (e) {
+        setError(e instanceof Error ? e.message : 'Upload failed.');
+      } finally {
+        setUploading(false);
+      }
+    },
+    [addClip],
+  );
+
+  return (
+    <>
+      <input
+        ref={fileInputRef}
+        type="file"
+        accept={SOUNDBOARD_ACCEPT}
+        hidden
+        onChange={(e) => {
+          handleFile(e.target.files?.[0]);
+          e.target.value = '';
+        }}
+      />
+      <PopOut
+        anchor={cords}
+        position="Top"
+        align="Center"
+        content={
+          <FocusTrap
+            focusTrapOptions={{
+              initialFocus: false,
+              onDeactivate: () => setCords(undefined),
+              clickOutsideDeactivates: true,
+              escapeDeactivates: stopPropagation,
+            }}
+          >
+            <Menu style={{ maxWidth: '320px' }}>
+              <Box direction="Column" gap="200" style={{ padding: config.space.S200 }}>
+                <Box alignItems="Center" justifyContent="SpaceBetween" gap="200">
+                  <Text size="L400">Soundboard</Text>
+                  <Chip
+                    variant="Secondary"
+                    radii="Pill"
+                    disabled={uploading || clips.length >= SOUNDBOARD_MAX_CLIPS}
+                    onClick={() => fileInputRef.current?.click()}
+                    before={
+                      uploading ? <Spinner size="100" /> : <Icon size="100" src={Icons.Plus} />
+                    }
+                  >
+                    <Text size="B300">Upload</Text>
+                  </Chip>
+                </Box>
+
+                {clips.length === 0 ? (
+                  <Text size="T200" priority="300">
+                    No clips yet. Upload a short audio clip (max 1 MB) to play it into the call.
+                    Clips sync across your devices.
+                  </Text>
+                ) : (
+                  <Box wrap="Wrap" gap="200">
+                    {clips.map((clip) => (
+                      <Box
+                        key={clip.id}
+                        direction="Column"
+                        gap="100"
+                        style={{ position: 'relative' }}
+                      >
+                        <Chip
+                          variant="SurfaceVariant"
+                          radii="300"
+                          disabled={busyId === clip.id}
+                          onClick={() => handlePlay(clip.id, clip.url)}
+                          before={
+                            busyId === clip.id ? (
+                              <Spinner size="100" />
+                            ) : (
+                              <Icon size="100" src={Icons.Play} />
+                            )
+                          }
+                          after={
+                            <Icon
+                              size="50"
+                              src={Icons.Cross}
+                              style={{ cursor: 'pointer' }}
+                              onClick={(e: React.MouseEvent) => {
+                                e.stopPropagation();
+                                removeClip(clip.id);
+                              }}
+                            />
+                          }
+                        >
+                          <Text size="B300" truncate style={{ maxWidth: '120px' }}>
+                            {clip.name}
+                          </Text>
+                        </Chip>
+                      </Box>
+                    ))}
+                  </Box>
+                )}
+
+                {error && (
+                  <Text size="T200" style={{ color: color.Critical.Main }}>
+                    {error}
+                  </Text>
+                )}
+              </Box>
+            </Menu>
+          </FocusTrap>
+        }
+      >
+        <TooltipProvider
+          tooltip={
+            <Tooltip>
+              <Text>Soundboard</Text>
+            </Tooltip>
+          }
+        >
+          {(triggerRef) => (
+            <IconButton
+              ref={triggerRef}
+              variant="Surface"
+              fill="Soft"
+              radii="400"
+              size="400"
+              onClick={handleOpen}
+              outlined
+              aria-label="Soundboard"
+              aria-expanded={!!cords}
+              aria-haspopup="menu"
+            >
+              <Icon size="400" src={Icons.BellRing} />
+            </IconButton>
+          )}
+        </TooltipProvider>
+      </PopOut>
+    </>
+  );
+}