Add more ready-to-run task templates

[BAKUGOS1]

Goal

Add reusable task JSON examples for common SaaS and CRM QA flows so new users can try QaAgent faster.

Suggested examples

• Logged-out marketing site smoke test
• Login + dashboard smoke test using env-backed credentials
• CRM lead creation flow with test data
• Table search/filter/sort/pagination flow

Done criteria

• Add examples under agent/tasks/
• Link them from README.md or docs/SAMPLE_REPORT.md
• Run npm run typecheck and npm run test:smoke
• Do not commit secrets, cookies, reports, screenshots, or real customer data