feat: rework runtime charts and fix time range propagation

Runtime page (AgentInstance):
- Rearrange charts: CPU, Memory, GC (top); Threads, Chunks Exported,
  Chunks Dropped (bottom). Removes throughput/error charts (belong on
  Dashboard, not Runtime).
- Pass global time range (from/to) to useAgentMetrics — charts now
  respect the time filter instead of always showing last 60 minutes.
- Bottom row (logs + timeline) fills remaining vertical space.

Dashboard L3:
- Processor metrics section fills remaining vertical space.
- Chart x-axis uses timestamps instead of bucket indices.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/src/api/queries/agent-metrics.ts

@@ -3,16 +3,24 @@ import { config } from '../../config';
 import { useAuthStore } from '../../auth/auth-store';
 import { useRefreshInterval } from './use-refresh-interval';
 
-export function useAgentMetrics(agentId: string | null, names: string[], buckets = 60) {
+export function useAgentMetrics(
+  agentId: string | null,
+  names: string[],
+  buckets = 60,
+  from?: string,
+  to?: string,
+) {
   const refetchInterval = useRefreshInterval(30_000);
   return useQuery({
-    queryKey: ['agent-metrics', agentId, names.join(','), buckets],
+    queryKey: ['agent-metrics', agentId, names.join(','), buckets, from, to],
     queryFn: async () => {
       const token = useAuthStore.getState().accessToken;
       const params = new URLSearchParams({
         names: names.join(','),
         buckets: String(buckets),
       });
+      if (from) params.set('from', from);
+      if (to) params.set('to', to);
       const res = await fetch(`${config.apiBaseUrl}/agents/${agentId}/metrics?${params}`, {
         headers: {
           Authorization: `Bearer ${token}`,