refactor(frontend): deduplicate CSS keyframes, unify types, extract format utils, add UI states, trim mock data

- Remove duplicate @keyframes pulse-* from 3 component files (already in nexus-tokens.css)
- Rename AgentDetail → AgentDetailData in dashboard types to avoid collision with types/agent.ts
- Extract shared formatNumber/initials/formatTime to utils/format.ts
- Simplify FlowBoard: use agentStore modal/selection getters instead of duplicating local state
- Add error banner + empty state to IrisChat; add loading skeleton + error/empty states to TaskStrip
- Remove 105-line unused mockAgents array from useFlowLayout
- Reduce operations store fallbacks from hardcoded preview data to minimal safe defaults
- Update operations store tests to match lean fallback structure
- Net: -73 lines, cleaner imports, fewer magic strings

frontend/tests/operations.test.ts

@@ -3,16 +3,23 @@ import { setActivePinia, createPinia } from 'pinia'
 import { useOperationsStore } from '../src/stores/operations'
 
 describe('operations store', () => {
-  it('initializes with fallback data', () => {
+  it('initializes with safe fallback structure', () => {
     setActivePinia(createPinia())
     const store = useOperationsStore()
-    expect(store.snapshot.metrics.activeAgents).toBeGreaterThan(0)
+    // Fallback provides a valid structure even when API is down
+    expect(store.snapshot).toBeDefined()
     expect(store.snapshot.runtime.runtime).toBe('OpenClaw')
+    expect(store.snapshot.metrics).toBeDefined()
+    expect(Array.isArray(store.snapshot.projects)).toBe(true)
+    expect(Array.isArray(store.snapshot.tasks)).toBe(true)
+    expect(Array.isArray(store.snapshot.activity)).toBe(true)
+    expect(Array.isArray(store.snapshot.models)).toBe(true)
   })
 
-  it('has routing targets', () => {
+  it('initializes routing as empty array', () => {
     setActivePinia(createPinia())
     const store = useOperationsStore()
-    expect(store.routing.length).toBeGreaterThan(0)
+    expect(Array.isArray(store.routing)).toBe(true)
+    expect(store.routing.length).toBe(0)
   })
 })