test: complete reviewer system e2e coverage

[alekhyasannoji-dev]

Summary

• Added comprehensive Playwright E2E coverage for the Reviewer System.
• Covered core moderator and expert review workflows.
• Added coverage for reviewer notifications and workflow transitions.
• Added document/source upload workflow coverage for PDF, DOC, and DOCX files.
• Added queue, data-integrity, and analytics coverage.
• Added staging E2E GitHub Actions configuration.
• Added QA documentation and test reporting.

Validation

• Playwright E2E: 98 tests passing
• Focused E2E: PASS
• Expert workflow: PASS
• Upload workflow: PASS
• Moderator workflow: PASS
• TypeScript: PASS
• Staging configuration: verified
• GitHub Actions: configured for staging deployment workflow triggers

Reviewer Workflow Covered

1. Moderator authentication and question queue
2. Expert allocation and notification
3. Expert assigned-question workflow
4. Expert answer submission
5. Reviewer notification
6. Moderator review and approval
7. Question closure and GDB transition
8. Source/document handling
9. Queue counts and data integrity
10. Analytics data surface

Known Limitations

• Stuck-question behavior can depend on backend scheduled processing.
• Reputation processing can depend on backend scheduled processing.
• Some seeded E2E scenarios consume seed data and may require reseeding before repeating them.
• Expert allocation is covered through the existing seeded/API workflow rather than a dedicated UI allocation test.

QA

See QA_REPORT.md and TEST_PLAN.md for detailed coverage, results, bugs, and known limitations.

Scope

No unrelated refactoring or destructive database changes were made as part of the final QA validation.