Implement the scraper history endpoint that returns past scrape run
records from the scraper_runs collection. Features include:
- GET /api/admin/scraper/history protected by requireAuth + requireAdmin
- Pagination via limit (1-100, default 30) and offset (default 0) params
- Input validation returning 400 for invalid limit/offset values
- Results sorted by startedAt descending (newest first)
- Graceful error handling returning 503 on database failures
- 20 new tests covering auth, pagination, validation, and error cases
## Summary
Implements the top-level runScrape() orchestration function that coordinates the entire scraper pipeline end-to-end.
### What it does
- Full pipeline orchestration: Calls fetchPage, parseUnits, convertDataTypes, upsertUnits, insertPrices, markStaleUnits, updateDailySummary in sequence
- dryRun mode: When enabled, parses and validates HTML but skips all database writes
- htmlContent injection: Accepts raw HTML directly, bypassing the fetch step
- New/rented unit calculation: Diffs currently scraped units against previously active units to determine newUnitsCount and rentedUnitsCount for the daily summary
- Run history recording: Every scrape (success or failure) is recorded to the scraper_runs collection via recordScraperRun()
- Structured logging: All pipeline stages log with jobId correlation for traceability
- Error resilience: Catches and handles errors at each stage, ensuring partial failures are logged and recorded
### Test coverage (15 tests)
- Full workflow with mocked dependencies
- Result structure validation and jobId generation
- dryRun mode skips DB writes
- htmlContent bypasses fetch
- Success and failure history recording
- Fetch error handling with retry exhaustion
- Database operation error handling
- New/rented unit count calculation
- Default and scheduled trigger types
- Empty HTML (no units) edge case
Reviewed-on: #16
Co-authored-by: Stephen Minakian <stephenminakian@gmail.com>
Co-committed-by: Stephen Minakian <stephenminakian@gmail.com>