feat(lab1): add CI smoke test workflow

[raaller]

Changes

• submissions/lab1.md — full triage report with real REMnux deployment data, security headers analysis, and 3 OWASP Top 10:2025 risk mappings
• .github/PULL_REQUEST_TEMPLATE.md — reusable PR template with 4 sections and 3-item checklist for all future labs
• .github/workflows/lab1-smoke.yml — GitHub Actions workflow that pulls Juice Shop v20.0.0 and verifies health via curl (bonus)

Testing

# Container health
docker ps | grep juice-shop
# 4bd57343c74b   bkimminich/juice-shop:v20.0.0   Up 14 minutes   127.0.0.1:3000->3000/tcp

# Homepage
curl -s -o /dev/null -w "HTTP %{http_code}\n" http://127.0.0.1:3000
# HTTP 200

# Product API
curl -s http://127.0.0.1:3000/api/Products | jq '.data | length'
# 46

# Version check
curl -s http://127.0.0.1:3000/rest/admin/application-version | jq
# {"version": "20.0.0"}

Artifacts & Screenshots

• Triage report: submissions/lab1.md
• PR template: .github/PULL_REQUEST_TEMPLATE.md
• CI workflow: .github/workflows/lab1-smoke.yml

Checklist

• Title is clear (feat(labN): style)

• No secrets/large temp files committed

• Submission file at submissions/labN.md exists

• Task 1 done — Juice Shop deployed, triage report in submissions/lab1.md

• Task 2 done — .github/PULL_REQUEST_TEMPLATE.md created

• Task 3 done — GitHub stars + follows complete

• Bonus done — lab1-smoke.yml runs green on this PR