feat: add trace log level to LogViewer

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

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

@@ -56,6 +56,11 @@
   background: color-mix(in srgb, var(--text-muted) 10%, transparent);
 }
 
+.levelTrace {
+  color: var(--text-faint);
+  background: color-mix(in srgb, var(--text-faint) 8%, transparent);
+}
+
 .message {
   font-size: 12px;
   font-family: var(--font-mono);

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

@@ -7,6 +7,7 @@ const entries: LogEntry[] = [
   { timestamp: '2024-01-15T10:30:05Z', level: 'warn', message: 'High memory usage' },
   { timestamp: '2024-01-15T10:30:10Z', level: 'error', message: 'Connection failed' },
   { timestamp: '2024-01-15T10:30:15Z', level: 'debug', message: 'Query executed in 3ms' },
+  { timestamp: '2024-01-15T10:30:20Z', level: 'trace', message: 'Entering handleRequest()' },
 ]
 
 describe('LogViewer', () => {
@@ -16,14 +17,16 @@ describe('LogViewer', () => {
     expect(screen.getByText('High memory usage')).toBeInTheDocument()
     expect(screen.getByText('Connection failed')).toBeInTheDocument()
     expect(screen.getByText('Query executed in 3ms')).toBeInTheDocument()
+    expect(screen.getByText('Entering handleRequest()')).toBeInTheDocument()
   })
 
-  it('renders level badges with correct text (INFO, WARN, ERROR, DEBUG)', () => {
+  it('renders level badges with correct text (INFO, WARN, ERROR, DEBUG, TRACE)', () => {
     render(<LogViewer entries={entries} />)
     expect(screen.getByText('INFO')).toBeInTheDocument()
     expect(screen.getByText('WARN')).toBeInTheDocument()
     expect(screen.getByText('ERROR')).toBeInTheDocument()
     expect(screen.getByText('DEBUG')).toBeInTheDocument()
+    expect(screen.getByText('TRACE')).toBeInTheDocument()
   })
 
   it('renders with custom maxHeight (number)', () => {

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

@@ -3,7 +3,7 @@ import styles from './LogViewer.module.css'
 
 export interface LogEntry {
   timestamp: string
-  level: 'info' | 'warn' | 'error' | 'debug'
+  level: 'info' | 'warn' | 'error' | 'debug' | 'trace'
   message: string
 }
 
@@ -18,6 +18,7 @@ const LEVEL_CLASS: Record<LogEntry['level'], string> = {
   warn: styles.levelWarn,
   error: styles.levelError,
   debug: styles.levelDebug,
+  trace: styles.levelTrace,
 }
 
 function formatTime(iso: string): string {