feat(web): add Fleet dashboard view for cross-instance observability

Adds a new /fleet route that shows a fleet-wide overview of all
configured Honcho instances. Each row renders per-instance metrics
(workspace count, total conclusions, queue activity, last seen, health)
by fanning out scoped fetches via createScopedClient, and aggregates
into top-level metric cards.

Reuses the Phase 2 scoped-client pattern. Extends compareQueries.ts
with useScopedQueueStatus and useScopedConclusionsCount, plus option
builders so useQueries can fan out per-workspace requests inside
FleetRow without duplicating query logic.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/web/src/api/compareQueries.ts

@@ -16,6 +16,9 @@ const CK = {
 		["compare", instId, "peer-representation", wsId, pId] as const,
 	peerCard: (instId: string, wsId: string, pId: string) =>
 		["compare", instId, "peer-card", wsId, pId] as const,
+	queueStatus: (instId: string, wsId: string) => ["compare", instId, "queue-status", wsId] as const,
+	conclusionsCount: (instId: string, wsId: string) =>
+		["compare", instId, "conclusions-count", wsId] as const,
 };
 
 export function useScopedWorkspaces(instance: Instance, page = 1, pageSize = 20) {
@@ -83,3 +86,43 @@ export function useScopedPeerCard(instance: Instance, workspaceId: string, peerI
 		enabled: Boolean(workspaceId) && Boolean(peerId),
 	});
 }
+
+// Option builders — used by both single-fetch hooks and useQueries fan-out (e.g. Fleet view).
+
+export function scopedQueueStatusOptions(instance: Instance, workspaceId: string) {
+	return {
+		queryKey: CK.queueStatus(instance.id, workspaceId),
+		queryFn: async () => {
+			const client = createScopedClient(instance);
+			const { data, error } = await client.GET("/v3/workspaces/{workspace_id}/queue/status", {
+				params: { path: { workspace_id: workspaceId } },
+			});
+			return data ?? err(error);
+		},
+		enabled: Boolean(workspaceId),
+		refetchInterval: 10_000,
+	} as const;
+}
+
+export function scopedConclusionsCountOptions(instance: Instance, workspaceId: string) {
+	return {
+		queryKey: CK.conclusionsCount(instance.id, workspaceId),
+		queryFn: async () => {
+			const client = createScopedClient(instance);
+			const { data, error } = await client.POST("/v3/workspaces/{workspace_id}/conclusions/list", {
+				params: { path: { workspace_id: workspaceId }, query: { page: 1, size: 1 } },
+				body: {},
+			});
+			return data ?? err(error);
+		},
+		enabled: Boolean(workspaceId),
+	} as const;
+}
+
+export function useScopedQueueStatus(instance: Instance, workspaceId: string) {
+	return useQuery(scopedQueueStatusOptions(instance, workspaceId));
+}
+
+export function useScopedConclusionsCount(instance: Instance, workspaceId: string) {
+	return useQuery(scopedConclusionsCountOptions(instance, workspaceId));
+}