Add test coverage checklist, report template, and stack matrix for ecommerce project

- Created a test coverage checklist to ensure comprehensive testing of backend and frontend components.
- Added a test report template to standardize reporting on test execution results and gaps.
- Introduced a test stack matrix to guide the selection of testing tools and frameworks for backend and frontend.
- Established a skill for repairing failing tests, including a failure triage checklist and a test repair template.
- Documented recommended MCP stack for ecommerce development with FastAPI and React/Next.js.
- Developed a detailed README outlining the project structure, agent capabilities, and recommended workflows.
- Compiled a comprehensive workflow guide detailing step-by-step commands for project setup, testing, and SEO implementation.

site-fullstack/.github/skills/ecommerce-seo-strategy/assets/internal-linking-playbook.md

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+# Internal Linking Playbook
+
+## Core principles
+- Link from high-authority pages to priority commercial pages.
+- Use consistent anchor language tied to real user phrasing.
+- Keep internal links helpful for users, not mechanically stuffed.
+
+## Required link systems
+- Global navigation to top categories and collections.
+- Breadcrumbs on category, collection, brand, and product pages.
+- Related products and related categories modules.
+- Editorial links from guides, FAQs, and comparison content to money pages.
+- Cross-links between complementary categories when intent overlaps.
+
+## Priority rules
+- Important categories should be reachable in few clicks.
+- New seasonal or campaign pages need fast internal linking support.
+- Orphan pages are not acceptable for strategic landing pages.