fix(rooms): upgrading a room keeps its Lotus settings (#327)

POST /rooms/{id}/upgrade copies only Synapse's fixed list of state, so an
upgrade silently dropped everything Lotus keeps in room state: an
audio-only voice channel became camera/screenshare-allowed, user limits
and bitrate caps vanished, the soundboard pack was lost, and a room set
to delete messages after 7 days kept new ones forever.

RoomUpgrade now reads the client-owned state first (utils/roomUpgradeState,
unit-tested: io.lotus.*, m.room.retention, role tags, room emoji packs)
and re-creates it in the replacement room; a partial copy is reported in
the dialog instead of closing silently.

Verified headless through the UI (v10 room with voice limit, quality
policy, a soundboard pack and retention → upgrade): before, none
survived; now all four are in the new room.

Follow-up (not here): for spaces, the children's m.space.parent still
point at the old space.

Fixes #327

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017PCb59uY3UKqDqt7B6hzd5

src/app/features/common-settings/general/RoomUpgrade.tsx

@@ -40,6 +40,7 @@ import { creatorsSupported } from '../../../utils/matrix';
 import { useRoomCreators } from '../../../hooks/useRoomCreators';
 import { BreakWord } from '../../../styles/Text.css';
 import { useModalStyle } from '../../../hooks/useModalStyle';
+import { stateToCarry } from '../../../utils/roomUpgradeState';
 
 function RoomUpgradeDialog({ requestClose }: { requestClose: () => void }) {
   const mx = useMatrixClient();
@@ -63,10 +64,41 @@ function RoomUpgradeDialog({ requestClose }: { requestClose: () => void }) {
   const [upgradeState, upgrade] = useAsyncCallback(
     useCallback(
       async (version: string, newAdditionalCreators?: string[]) => {
-        await mx.http.authedRequest(Method.Post, `/rooms/${room.roomId}/upgrade`, undefined, {
-          new_version: version,
-          additional_creators: newAdditionalCreators,
-        });
+        // [Gitea #327] Synapse doesn't copy Lotus room state (voice limit, call
+        // policy, soundboard, retention, role tags, emoji packs) into the
+        // replacement room: read it first, re-create it after the upgrade.
+        const carried = stateToCarry(
+          Array.from(room.currentState.events.values()).flatMap((byKey) =>
+            Array.from(byKey.values()),
+          ),
+        );
+        const res = await mx.http.authedRequest<{ replacement_room?: string }>(
+          Method.Post,
+          `/rooms/${room.roomId}/upgrade`,
+          undefined,
+          {
+            new_version: version,
+            additional_creators: newAdditionalCreators,
+          },
+        );
+        const newRoomId = res?.replacement_room;
+        if (!newRoomId || carried.length === 0) return;
+        const results = await Promise.allSettled(
+          carried.map((st) =>
+            mx.http.authedRequest(
+              Method.Put,
+              `/rooms/${encodeURIComponent(newRoomId)}/state/${encodeURIComponent(st.type)}/${encodeURIComponent(st.stateKey)}`,
+              undefined,
+              st.content,
+            ),
+          ),
+        );
+        const failed = results.filter((r) => r.status === 'rejected').length;
+        if (failed > 0) {
+          throw new Error(
+            `Room upgraded, but ${failed} of ${carried.length} Lotus settings (voice limit, call policy, soundboard, retention…) could not be copied to the new room.`,
+          );
+        }
       },
       [mx, room],
     ),