oikos phase 0: ontology + inventory + policy seeds, OpenAPI contract, ADRs

- seeds/ontology.yaml: 59 entity types (5 abstract, is-a hierarchy), 46
  relationship types with cardinality, 6 lifecycles with terminal states
  and named precondition checks
- seeds/inventory.yaml: 110 entities / 142 relationships translated from
  legacy inventory.yaml (fleet, services, ingress, storage, governance,
  archaeology); thin spots marked for backfill
- seeds/policy.yaml: 4 risk classes, 27 approval rules (hierarchy-aware,
  per-entity overrides), autonomy kill-switch off (cold start)
- api/openapi.yaml: full v1 REST contract (40 paths), RFC 9457 errors,
  cursor pagination, idempotency, ETag/If-Match, scopes; redocly-clean
- docs/adr/0001-0010: initial architecture decision records
- scripts/validate-seeds.py: Phase 0 gate — hierarchy, lifecycles,
  endpoints, cardinality, policy cross-refs (0 errors)
- plan: layer CHECK gains 'meta' (root type), cardinality gains
  'many-to-one'

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs/adr/0001-go-single-binary.md

@@ -0,0 +1,23 @@
+# ADR 0001 — Go with single-binary role packaging
+
+Status: accepted (2026-07-07) · Plan: rev 3, R3-4
+
+## Context
+The OS has three long-running roles (api, scheduler+actuator+learning,
+notifier) plus one-shot jobs (migrate, seed, export). Rev 2 planned three
+binaries with three Dockerfiles.
+
+## Decision
+One Go binary `oikos` with role subcommands (`oikos api | scheduler |
+notifier | all | migrate | seed | export`), one multi-stage Dockerfile, one
+image tagged `oikos:<git-sha>`. Compose runs the image N times with
+different commands (Loki/Temporal pattern). Go over Python for static
+typing, small static binaries (CGO_ENABLED=0, distroless), and goroutines
+for concurrent probes.
+
+## Consequences
+- One build, guaranteed version consistency across roles, trivial local dev
+  (`oikos all`), simpler rollback (retag one image).
+- Full rewrite of ~4,400 Python lines (logic carries over per plan reuse map).
+- All roles share a dependency set; image is slightly larger than per-role
+  minimal images — accepted.