fix(ui): reconcile active operations from local scans

Local operation spinners were driven by begin, finish, and failure event
history. If one of those lifecycle events was missed, the Tauri bridge could
keep a stale active operation and the React state would keep showing an
in-progress spinner until restart.

Peer local scan updates now carry an authoritative active-operation snapshot.
The peer still suppresses active game roots from peer-facing library deltas,
but it emits LocalGamesUpdated to the UI even when no library delta changed so
the snapshot can clear stale state after rollback or completion. The Tauri
bridge replaces its active-operation map from that snapshot, emits it with the
games-list payload, and the React merge uses it to restore download, install,
update, and uninstall spinners from current peer state rather than event
history alone.

This also enables the Tauri lib unit-test target so the reconciliation helper
can stay covered by the workspace test recipe.

Test Plan:
- git diff --check
- just fmt
- just clippy
- just test

Follow-up-Plan: FOLLOW_UP_2.md

crates/lanspread-tauri-deno-ts/src/App.tsx

@@ -55,6 +55,23 @@ enum GameAvailability {
     LocalOnly = 'LocalOnly',
 }
 
+enum ActiveOperationKind {
+    Downloading = 'Downloading',
+    Installing = 'Installing',
+    Updating = 'Updating',
+    Uninstalling = 'Uninstalling',
+}
+
+interface ActiveOperation {
+    id: string;
+    operation: ActiveOperationKind;
+}
+
+interface GamesListPayload {
+    games: Game[];
+    active_operations?: ActiveOperation[];
+}
+
 interface GameThumbnailProps {
     gameId: string;
     alt: string;
@@ -95,27 +112,78 @@ const IN_PROGRESS_INSTALL_STATUSES = new Set<InstallStatus>([
     InstallStatus.Uninstalling,
 ]);
 
+const RECONCILED_OPERATION_STATUSES = new Set<InstallStatus>([
+    InstallStatus.Downloading,
+    InstallStatus.Installing,
+    InstallStatus.Uninstalling,
+]);
+
 const isInProgressInstallStatus = (status: InstallStatus): boolean => {
     return IN_PROGRESS_INSTALL_STATUSES.has(status);
 };
 
-const mergeGameUpdate = (game: Game, previous?: Game): Game => {
+const isReconciledOperationStatus = (status: InstallStatus): boolean => {
+    return RECONCILED_OPERATION_STATUSES.has(status);
+};
+
+const installStatusFromActiveOperation = (operation: ActiveOperationKind): InstallStatus => {
+    switch (operation) {
+        case ActiveOperationKind.Downloading:
+            return InstallStatus.Downloading;
+        case ActiveOperationKind.Installing:
+        case ActiveOperationKind.Updating:
+            return InstallStatus.Installing;
+        case ActiveOperationKind.Uninstalling:
+            return InstallStatus.Uninstalling;
+    }
+};
+
+const activeStatusById = (activeOperations: ActiveOperation[] = []): Map<string, InstallStatus> => {
+    return new Map(activeOperations.map(operation => [
+        operation.id,
+        installStatusFromActiveOperation(operation.operation),
+    ]));
+};
+
+const normalizeGamesListPayload = (payload: GamesListPayload | Game[]): GamesListPayload => {
+    if (Array.isArray(payload)) {
+        return { games: payload };
+    }
+    return payload;
+};
+
+const mergeGameUpdate = (
+    game: Game,
+    previous?: Game,
+    activeStatus?: InstallStatus,
+    hasAuthoritativeSnapshot = false,
+): Game => {
     let installStatus = InstallStatus.NotInstalled;
-    if (game.installed) {
+    if (activeStatus !== undefined) {
+        installStatus = activeStatus;
+    } else if (game.installed) {
         installStatus = InstallStatus.Installed;
-    } else if (previous && isInProgressInstallStatus(previous.install_status)) {
+    } else if (
+        previous
+        && isInProgressInstallStatus(previous.install_status)
+        && (!hasAuthoritativeSnapshot || previous.install_status === InstallStatus.CheckingPeers)
+    ) {
         installStatus = previous.install_status;
     }
 
     const localStateChanged = previous !== undefined
         && (previous.installed !== game.installed || previous.downloaded !== game.downloaded);
+    const activeStateReconciled = hasAuthoritativeSnapshot
+        && (activeStatus !== undefined
+            || (previous !== undefined && isReconciledOperationStatus(previous.install_status)));
+    const clearStatus = localStateChanged || activeStateReconciled;
 
     return {
         ...game,
         availability: game.availability ?? (game.downloaded ? GameAvailability.Ready : GameAvailability.LocalOnly),
         install_status: installStatus,
-        status_message: localStateChanged ? undefined : previous?.status_message,
-        status_level: localStateChanged ? undefined : previous?.status_level,
+        status_message: clearStatus ? undefined : previous?.status_message,
+        status_level: clearStatus ? undefined : previous?.status_level,
         peer_count: game.peer_count ?? 0,
     };
 };
@@ -356,11 +424,19 @@ const App = () => {
                 // Listen for games-list-updated events
                 const unlisten_games = await listen('games-list-updated', (event) => {
                     console.log('🗲 Received games-list-updated event');
-                    const games = event.payload as Game[];
+                    const payload = normalizeGamesListPayload(event.payload as GamesListPayload | Game[]);
+                    const games = payload.games;
+                    const activeStatuses = activeStatusById(payload.active_operations);
+                    const hasAuthoritativeSnapshot = payload.active_operations !== undefined;
                     console.log(`🎮 ${games.length} Games received`);
                     setGameItems(prev => {
                         const previousById = new Map(prev.map(item => [item.id, item]));
-                        return games.map(game => mergeGameUpdate(game, previousById.get(game.id)));
+                        return games.map(game => mergeGameUpdate(
+                            game,
+                            previousById.get(game.id),
+                            activeStatuses.get(game.id),
+                            hasAuthoritativeSnapshot,
+                        ));
                     });
                     void getInitialGameDir();
                 });