test(integration): port delete operations tests to self-contained framework

Ports 8_deleteTests.mjs (76 tests) to the new per-suite isolated Harper
instance pattern. Creates its own northnwd.employees and dev.rando fixtures
in before(); uses awaitJob/getJobId from utils/operations.mjs for async
job polling.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: kriszyp