feat: Breadcrumb and Tabs composites

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

src/design-system/composites/Breadcrumb/Breadcrumb.module.css

@@ -0,0 +1,35 @@
+.list {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  list-style: none;
+  font-size: 13px;
+  color: var(--text-muted);
+  flex-wrap: wrap;
+}
+
+.item {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+}
+
+.sep {
+  color: var(--text-faint);
+  font-size: 11px;
+}
+
+.link {
+  color: var(--text-muted);
+  text-decoration: none;
+  transition: color 0.12s;
+}
+
+.link:hover {
+  color: var(--text-secondary);
+}
+
+.active {
+  color: var(--text-primary);
+  font-weight: 600;
+}

src/design-system/composites/Breadcrumb/Breadcrumb.tsx

@@ -0,0 +1,37 @@
+import styles from './Breadcrumb.module.css'
+
+interface BreadcrumbItem {
+  label: string
+  href?: string
+}
+
+interface BreadcrumbProps {
+  items: BreadcrumbItem[]
+  className?: string
+}
+
+export function Breadcrumb({ items, className }: BreadcrumbProps) {
+  return (
+    <nav aria-label="Breadcrumb" className={className}>
+      <ol className={styles.list}>
+        {items.map((item, index) => {
+          const isLast = index === items.length - 1
+          return (
+            <li key={index} className={styles.item}>
+              {index > 0 && <span className={styles.sep}>/</span>}
+              {isLast ? (
+                <span className={styles.active}>{item.label}</span>
+              ) : item.href ? (
+                <a href={item.href} className={styles.link}>
+                  {item.label}
+                </a>
+              ) : (
+                <span className={styles.link}>{item.label}</span>
+              )}
+            </li>
+          )
+        })}
+      </ol>
+    </nav>
+  )
+}

src/design-system/composites/Tabs/Tabs.module.css

@@ -0,0 +1,52 @@
+.bar {
+  display: flex;
+  align-items: center;
+  border-bottom: 1px solid var(--border-subtle);
+  gap: 0;
+}
+
+.tab {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  padding: 9px 16px;
+  font-size: 13px;
+  font-weight: 500;
+  font-family: var(--font-body);
+  color: var(--text-muted);
+  background: none;
+  border: none;
+  border-bottom: 2px solid transparent;
+  margin-bottom: -1px;
+  cursor: pointer;
+  transition: color 0.15s, border-color 0.15s;
+  white-space: nowrap;
+}
+
+.tab:hover {
+  color: var(--text-secondary);
+}
+
+.tab.active {
+  color: var(--amber);
+  border-bottom-color: var(--amber);
+}
+
+.label {
+  /* no special styles needed */
+}
+
+.count {
+  font-family: var(--font-mono);
+  font-size: 10px;
+  background: var(--bg-inset);
+  color: var(--text-muted);
+  padding: 1px 5px;
+  border-radius: 10px;
+  line-height: 1.4;
+}
+
+.tab.active .count {
+  background: var(--amber-bg);
+  color: var(--amber);
+}

src/design-system/composites/Tabs/Tabs.test.tsx

@@ -0,0 +1,31 @@
+import { describe, it, expect, vi } from 'vitest'
+import { render, screen } from '@testing-library/react'
+import userEvent from '@testing-library/user-event'
+import { Tabs } from './Tabs'
+
+describe('Tabs', () => {
+  const tabs = [
+    { label: 'All', count: 14, value: 'all' },
+    { label: 'Executions', count: 8, value: 'executions' },
+    { label: 'Routes', count: 3, value: 'routes' },
+  ]
+
+  it('renders all tab labels', () => {
+    render(<Tabs tabs={tabs} active="all" onChange={() => {}} />)
+    expect(screen.getByText('All')).toBeInTheDocument()
+    expect(screen.getByText('Executions')).toBeInTheDocument()
+  })
+
+  it('shows count badges', () => {
+    render(<Tabs tabs={tabs} active="all" onChange={() => {}} />)
+    expect(screen.getByText('14')).toBeInTheDocument()
+  })
+
+  it('calls onChange with tab value', async () => {
+    const onChange = vi.fn()
+    const user = userEvent.setup()
+    render(<Tabs tabs={tabs} active="all" onChange={onChange} />)
+    await user.click(screen.getByText('Routes'))
+    expect(onChange).toHaveBeenCalledWith('routes')
+  })
+})

src/design-system/composites/Tabs/Tabs.tsx

@@ -0,0 +1,36 @@
+import styles from './Tabs.module.css'
+
+interface TabItem {
+  label: string
+  count?: number
+  value: string
+}
+
+interface TabsProps {
+  tabs: TabItem[]
+  active: string
+  onChange: (value: string) => void
+  className?: string
+}
+
+export function Tabs({ tabs, active, onChange, className }: TabsProps) {
+  return (
+    <div className={`${styles.bar} ${className ?? ''}`} role="tablist">
+      {tabs.map((tab) => (
+        <button
+          key={tab.value}
+          role="tab"
+          aria-selected={tab.value === active}
+          className={`${styles.tab} ${tab.value === active ? styles.active : ''}`}
+          onClick={() => onChange(tab.value)}
+          type="button"
+        >
+          <span className={styles.label}>{tab.label}</span>
+          {tab.count !== undefined && (
+            <span className={styles.count}>{tab.count}</span>
+          )}
+        </button>
+      ))}
+    </div>
+  )
+}