Update four existing specs (overview, server, napi-and-pubsub, call-protocol) to
reflect Phase 0 decisions: three-layer model, IdentityProvider, ForwardingPolicy,
OperationEnv, static/dynamic config split. Review all 9 Phase 0a ADRs (026-034)
for consistency. Fix 4 critical issues from architecture review: missing OQ-SVC-05
in open-questions.md, deprecated hub terminology, undefined AuthService and noq
terms. Replace inline OQ text with cross-references per format rules. Add
ConfigServiceImpl definition to configuration.md. Port absolute workspace paths
to project-relative links by copying referenced docs (feasibility, certbot,
fail2ban, event_source_types) into docs/research/.
