Add React UI with Execution Explorer, auth, and standalone deployment

- Scaffold Vite + React + TypeScript frontend in ui/ with full design
  system (dark/light themes) matching the HTML mockups
- Implement Execution Explorer page: search filters, results table with
  expandable processor tree and exchange detail sidebar, pagination
- Add UI authentication: UiAuthController (login/refresh endpoints),
  JWT filter handles ui: subject prefix, CORS configuration
- Shared components: StatusPill, DurationBar, StatCard, AppBadge,
  FilterChip, Pagination — all using CSS Modules with design tokens
- API client layer: openapi-fetch with auth middleware, TanStack Query
  hooks for search/detail/snapshot queries, Zustand for state
- Standalone deployment: Nginx Dockerfile, K8s Deployment + ConfigMap +
  NodePort (30080), runtime config.js for API base URL
- Embedded mode: maven-resources-plugin copies ui/dist into JAR static
  resources, SPA forward controller for client-side routing
- CI/CD: UI build step, Docker build/push for server-ui image, K8s
  deploy step for UI, UI credential secrets

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

ui/src/auth/LoginPage.module.css

@@ -0,0 +1,103 @@
+.page {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  min-height: 100vh;
+  position: relative;
+  z-index: 1;
+}
+
+.card {
+  background: var(--bg-surface);
+  border: 1px solid var(--border-subtle);
+  border-radius: var(--radius-lg);
+  padding: 40px;
+  width: 100%;
+  max-width: 400px;
+  animation: fadeIn 0.3s ease-out both;
+}
+
+.logo {
+  font-family: var(--font-mono);
+  font-weight: 600;
+  font-size: 20px;
+  color: var(--amber);
+  letter-spacing: -0.5px;
+  display: flex;
+  align-items: center;
+  gap: 10px;
+  margin-bottom: 8px;
+}
+
+.subtitle {
+  font-size: 13px;
+  color: var(--text-muted);
+  margin-bottom: 28px;
+}
+
+.field {
+  margin-bottom: 16px;
+}
+
+.label {
+  display: block;
+  font-size: 11px;
+  font-weight: 600;
+  text-transform: uppercase;
+  letter-spacing: 0.8px;
+  color: var(--text-muted);
+  margin-bottom: 6px;
+}
+
+.input {
+  width: 100%;
+  background: var(--bg-base);
+  border: 1px solid var(--border);
+  border-radius: var(--radius-sm);
+  padding: 10px 14px;
+  color: var(--text-primary);
+  font-family: var(--font-mono);
+  font-size: 13px;
+  outline: none;
+  transition: border-color 0.2s, box-shadow 0.2s;
+}
+
+.input:focus {
+  border-color: var(--amber-dim);
+  box-shadow: 0 0 0 3px var(--amber-glow);
+}
+
+.submit {
+  width: 100%;
+  margin-top: 8px;
+  padding: 10px 16px;
+  border-radius: var(--radius-sm);
+  border: 1px solid var(--amber);
+  background: var(--amber);
+  color: #0a0e17;
+  font-family: var(--font-body);
+  font-size: 14px;
+  font-weight: 600;
+  cursor: pointer;
+  transition: all 0.15s;
+}
+
+.submit:hover {
+  background: var(--amber-hover);
+  border-color: var(--amber-hover);
+}
+
+.submit:disabled {
+  opacity: 0.5;
+  cursor: not-allowed;
+}
+
+.error {
+  margin-top: 12px;
+  padding: 10px 12px;
+  background: var(--rose-glow);
+  border: 1px solid rgba(244, 63, 94, 0.2);
+  border-radius: var(--radius-sm);
+  font-size: 13px;
+  color: var(--rose);
+}