Create example PRD for e-commerce project

[xiapeli]

Summary

Add a complete example PRD (Product Requirements Document) that demonstrates how Jobim's multi-agent pipeline works end-to-end. The example should use an e-commerce project as the domain, showing how each pipeline phase and agent contributes to the final product.

Suggested Approach

1. Create `examples/ecommerce-prd/` directory
2. Include documents for each pipeline phase:
   • `01-discovery.md` — Scout agent output: market research, competitor analysis
   • `02-prototype.md` — Builder/Designer agent output: wireframes description, tech stack
   • `03-production.md` — Builder/Tester agent output: implementation plan, test strategy
   • `04-ship.md` — Shipper agent output: deployment checklist, infrastructure
   • `05-launch.md` — Launcher agent output: go-to-market plan, metrics to track
3. Add a `README.md` in the example directory explaining the flow

E-Commerce Scope Suggestion

Keep it focused. For example, a simple product catalog with:

• Product listing page
• Product detail page
• Shopping cart
• Checkout flow (mock payment)

Acceptance Criteria

• Example directory created with all phase documents
• Each document shows realistic agent input/output
• README explains how to follow the example
• Documents reference each other (upstream/downstream)
• The example is self-contained and understandable without prior Jobim knowledge

Notes

• This example will serve as the primary onboarding resource for new contributors
• Keep content practical and realistic, not placeholder text