fix(runtime): keep shared artifacts optional

docs/adr/0011-laboratory-plugin-runtime-handshake-and-transport-seam.md

@@ -64,7 +64,10 @@ separate future gate.
 
 `GET /api/v1/device-plugin-runtimes` exposes the small lifecycle snapshots. The
 main health response includes ready/total runtime counts as one component beside
-recording-cache, shared-artifact, media-tool and catalog-reconciler readiness.
+recording-cache, optional shared-artifact capability, media-tool and
+catalog-reconciler readiness. A missing optional shared-artifact provider does
+not degrade the complete local contour.
+
 The plugin values still do not claim device connectivity, sensor health,
 process containment or durable supervision.
 

docs/adr/0022-operator-surface-ownership.md

@@ -78,7 +78,7 @@ Contour health reads only live contracts:
 - current Mission Runtime state for active device and perception metrics.
 
 The base health contract now separates local operational readiness from
-production shared-artifact readiness and reports bounded cache, catalog
+optional shared-artifact capability and reports bounded cache, catalog
 reconciler, media-tool and Map Gateway configuration states. It performs no
 remote fan-out and never invents Worker 006 or device health.
 

docs/adr/0033-central-session-artifacts-and-bounded-host-cache.md

@@ -5,17 +5,18 @@ Status: accepted and implemented
 
 ## Decision
 
-Mission Core stores portable recorded-session products in a provider-neutral,
-content-addressed artifact store. The current central provider is the existing
-Synology SMB mount:
+Mission Core can exchange portable recorded-session products through an
+optional provider-neutral, content-addressed artifact gateway. The canonical
+current operator contour is local and complete without a shared store. An
+external filesystem provider is an auxiliary transport/prefetch capability,
+not an operational-readiness dependency and not a production topology
+decision.
 
-```text
-/Volumes/docker/nodedc-mission-core/artifact-store
-```
-
-This is product runtime data. It is not a deploy artifact, a Map Gateway cache,
-a Device Plane package, or a new Docker service. Authentication remains owned
-by the operating-system SMB mount; Mission Core does not receive a NAS password.
+The historical RAVNOVES00 migration acceptance used an existing SMB-backed
+filesystem as one experimental provider. That provider, its mount and its host
+configuration are outside the current Mission Core runtime contract. Mission
+Core does not own its authentication, does not require it at startup and does
+not receive a NAS password.
 
 Every immutable object is stored under:
 
@@ -55,7 +56,7 @@ MISSIONCORE_ARTIFACT_CACHE_MAX_BYTES
 MISSIONCORE_ARTIFACT_CACHE_FREE_SPACE_RESERVE_BYTES
 ```
 
-The central root is configured with:
+An optional shared root is configured explicitly with:
 
 ```text
 MISSIONCORE_ARTIFACT_STORE_ROOT
@@ -115,16 +116,19 @@ When the central root is unavailable:
 `GET /api/health` exposes the effective shared/standalone mode, central-store
 availability, bounded CAS and RRD-cache occupancy, media-tool availability and
 the background catalog reconciler state without disclosing filesystem paths.
-Operational readiness remains distinct from production shared-artifact
-readiness so an offline, already pinned field host stays observable rather than
-being mistaken for a fully connected host.
+`GET /api/health` reports local operational readiness independently. Optional
+shared artifacts are exposed as a non-required capability with separate
+`configured` and `ready` values. Their absence or temporary unavailability does
+not degrade a healthy local contour. When an operator explicitly configures
+that capability, its fail-closed cache-miss semantics still apply to artifacts
+that were expected from the configured gateway.
 
 ## RAVNOVES00 migration acceptance
 
 The source session is `20260720T065719Z_viewer_live`, displayed as
 `RAVNOVES00`.
 
-The accepted central reference currently points to:
+The reference used by that bounded migration acceptance pointed to:
 
 ```text
 092f758c09965be98fd76d8191474c528ee20540dce5f4761c2a087f6056a6d5

src/k1link/artifact_cli.py

@@ -1,4 +1,4 @@
-"""Operator commands for the Mission Core central artifact gateway."""
+"""Operator commands for the optional Mission Core artifact gateway."""
 
 from __future__ import annotations
 

src/k1link/artifact_gateway.py

@@ -1,4 +1,4 @@
-"""Content-addressed central artifacts with a bounded, offline-capable host cache."""
+"""Optional content-addressed artifact exchange with a bounded local cache."""
 
 from __future__ import annotations
 

src/k1link/web/runtime_readiness.py

@@ -100,8 +100,9 @@ def build_runtime_readiness(
             "central_available": None,
         }
         shared_artifacts_ready = False
-        shared_artifact_degraded = False
+        shared_artifacts_configured = False
     else:
+        shared_artifacts_configured = True
         try:
             artifact = artifact_gateway.status()
             cache = artifact.cache
@@ -127,7 +128,6 @@ def build_runtime_readiness(
                 },
             }
             shared_artifacts_ready = artifact.central_status == "ready"
-            shared_artifact_degraded = not shared_artifacts_ready
         except (OSError, RuntimeError):
             artifact_document = {
                 "mode": "shared",
@@ -135,7 +135,6 @@ def build_runtime_readiness(
                 "central_available": False,
             }
             shared_artifacts_ready = False
-            shared_artifact_degraded = True
 
     media_tools_ready = ffmpeg_available and ffprobe_available
     reconciler_document = reconciler.snapshot()
@@ -151,11 +150,7 @@ def build_runtime_readiness(
         and media_tools_ready
         and reconciler_failures < 3
     )
-    degraded = (
-        shared_artifact_degraded
-        or reconciler_failures > 0
-        or not operational_ready
-    )
+    degraded = reconciler_failures > 0 or not operational_ready
     status = (
         "unavailable"
         if not operational_ready
@@ -170,9 +165,11 @@ def build_runtime_readiness(
         "version": version,
         "readiness": {
             "operational": operational_ready,
-            "production_shared_artifacts": (
-                operational_ready and shared_artifacts_ready
-            ),
+            "optional_shared_artifacts": {
+                "required": False,
+                "configured": shared_artifacts_configured,
+                "ready": shared_artifacts_ready,
+            },
         },
         "plugin_runtimes": {
             "ready": ready_runtime_count,

tests/test_runtime_readiness.py

@@ -57,7 +57,11 @@ def test_runtime_readiness_reports_shared_store_and_bounded_cache(
     assert document["status"] == "ok"
     assert document["readiness"] == {
         "operational": True,
-        "production_shared_artifacts": True,
+        "optional_shared_artifacts": {
+            "required": False,
+            "configured": True,
+            "ready": True,
+        },
     }
     components = document["components"]
     assert isinstance(components, dict)
@@ -85,16 +89,47 @@ def test_runtime_readiness_exposes_offline_cache_only_mode(
     document = _document(tmp_path, gateway=gateway, reconciler=reconciler)
 
     assert document["ok"] is True
-    assert document["status"] == "degraded"
+    assert document["status"] == "ok"
     assert document["readiness"] == {
         "operational": True,
-        "production_shared_artifacts": False,
+        "optional_shared_artifacts": {
+            "required": False,
+            "configured": True,
+            "ready": False,
+        },
     }
     components = document["components"]
     assert isinstance(components, dict)
     assert components["artifact_store"]["status"] == "offline-cache-only"
 
 
+def test_runtime_readiness_treats_standalone_as_complete_local_contour(
+    tmp_path: Path,
+) -> None:
+    reconciler = BackgroundReconcilerReadiness()
+    reconciler.record_success()
+
+    document = _document(tmp_path, gateway=None, reconciler=reconciler)
+
+    assert document["ok"] is True
+    assert document["status"] == "ok"
+    assert document["readiness"] == {
+        "operational": True,
+        "optional_shared_artifacts": {
+            "required": False,
+            "configured": False,
+            "ready": False,
+        },
+    }
+    components = document["components"]
+    assert isinstance(components, dict)
+    assert components["artifact_store"] == {
+        "mode": "standalone",
+        "status": "not-configured",
+        "central_available": None,
+    }
+
+
 def test_runtime_readiness_fails_after_repeated_reconciler_errors(
     tmp_path: Path,
 ) -> None: