feat(trajectory): implement trajectory step cell and layout with bilingual support

- Added TrajectoryCell, TrajectoryGroupHeader, and TrajectoryTurn components for rendering trajectory steps and groups.
- Introduced bilingual support with English and Chinese translations for trajectory notes.
- Updated conversation session models to include timestamps for various message types.
- Enhanced layout logic to handle expanded assistant blocks and tool results with duration metrics.
- Added CSS styles for new components to ensure proper display and alignment.

packages/client/ui-conversation/tests/chat-tool-row.spec.tsx

@@ -12,12 +12,13 @@ import type { ToolRowOwnerProps } from '@deepseek-ai/dsh-client-ui-conversation/
 
 const running = (over?: Partial<RunningToolCall>): RunningToolCall => ({
   callId: 'c1', name: 'bash', argsRaw: '{"command":"ls -la","description":"List files"}',
-  turn: 1, step: 1, callView: null, ...over,
+  turn: 1, step: 1, time: 1_000, callView: null, ...over,
 })
 
 const result = (over?: Partial<ToolResultNode>): ToolResultNode => ({
-  kind: 'tool-result', seq: 10, callId: 'c1',
+  kind: 'tool-result', seq: 10, time: 2_000, callId: 'c1',
   call: { name: 'bash', argsRaw: '{"command":"ls -la","description":"List files"}' },
+  callTime: 1_000,
   content: [], isError: false, callView: null, resultView: null, ...over,
 })