feat(kanban): add feature summary display and agent context info

Enhance Kanban cards to show comprehensive feature information:
- Add feature summary field to display completed work details
- Show agent context info (model, progress, tasks) on cards
- Display tool usage and token consumption metrics
- Add expandable summary dialog for detailed view
- Update prompts to require summary when marking features complete
- Improve UI for waiting_approval and verified states

Modified: kanban-card.tsx, board-view.tsx, feature-loader.js,
mcp-server-factory.js, prompt-builder.js, app-store.ts
Created: agent-context-parser.ts

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4 <noreply@anthropic.com>

app/src/store/app-store.ts

@@ -61,6 +61,7 @@ export interface Feature {
   imagePaths?: FeatureImagePath[]; // Paths to temp files for agent context
   startedAt?: string; // ISO timestamp for when the card moved to in_progress
   skipTests?: boolean; // When true, skip TDD approach and require manual verification
+  summary?: string; // Summary of what was done/modified by the agent
 }
 
 export interface AppState {