Adds CONTINUOUS_INTEGRATION.md (mirrors HOP's CI doc structure), links it
from README, and records the CI changelog entry plus the follow-up review's
open findings (scheduler crash-loop, System.gc(), connection pooling, the
PostgresService field-routing invariant, and the mislabeled main-method
"tests") in the roadmap's Phase 2/Phase 5 checklists.
b0txec