docs: write Phase 0 architecture foundation — ADRs 026-034, spec docs, and task updates
Phase 0a — ADRs (9 new):
- ADR-026: Transport/interface separation (three-layer model)
- ADR-027: Crate decomposition (core, secret, storage, flowgraph, napi, CLI)
- ADR-028: Auth as irpc service (AuthProtocol behind feature flag)
- ADR-029: Identity as core type (Identity + IdentityProvider in alknet-core)
- ADR-030: Static/dynamic config split (ArcSwap, ConfigReloadHandle)
- ADR-031: Forwarding policy (rule-based allow/deny, TransportKind-aware)
- ADR-032: Event boundary discipline (domain, irpc, call protocol boundaries)
- ADR-033: OperationEnv universal composition (three dispatch paths)
- ADR-034: Head/worker terminology (replace hub/spoke)
Phase 0b — New spec documents (7):
- identity.md, services.md, interface.md, configuration.md,
storage.md, flowgraph.md, secret-service.md
Updated existing docs:
- auth.md: reference identity.md for canonical definitions, add AuthProtocol
- open-questions.md: resolve OQ-12, OQ-16, OQ-18, OQ-22, OQ-23-25
- README.md: add all new docs, ADRs 026-034
Marked 19 architecture tasks as completed.
glm-5.1
19b3d3a078