AMPR-219: T6 — Activate the relay in the CODE production agent path

[wow-miley]

Summary

Activates the capability/cost-aware CognitiveRelay in one real bundled agent path — SparkBasedAgent.Code (the agent AgentFactory builds for AgentType.CODE) — so the full selection seam runs live at least once: AgentDefinition.minimumRung floor → RoutingContext → CognitiveRelayImpl.resolveWithMetadata → model-keyed cost-aware selection → outbound client. Manual constructor injection, no Koin.

Closes the antipattern AMPR-219 targets: the tier system is no longer assertion-only — it has a live consumer, validated end-to-end, with a recorded go/no-go verdict.

Resolves AMPR-219 / #575.

Changes

• SparkBasedAgent.kt — new _cognitiveRelay / _minimumRung constructor params, threaded into the agentConfiguration getter (cognitiveRelay, AgentDefinition.Custom(minimumRung = …)) and exposed on the Code factory.
• CapabilityRoutingDefaults.kt (new) — one ByCapability rule per bundled cloud model, in lockstep with the InMemoryModelDescriptorRegistry seed. Without it any declared floor would always be FloorUnmet.
• AgentFactory.kt — builds a real CognitiveRelayImpl + InMemoryModelDescriptorRegistry over the shared eventSerialBus, wired into the CODE path only (DEFAULT_CODE_AGENT_RUNG = THREE). PRODUCT / PROJECT / QUALITY stay dormant (null relay).
• AgentDefinition.kt — Custom factory now carries minimumRung (defaults null → non-breaking for existing callers).

Validation (end-to-end, not unit-only)

SparkBasedAgentRelayActivationTest drives a real SparkBasedAgent.Code through its own callLLM seam:

1. Wiring — Code(...) sets cognitiveRelay and declares minimumRung = THREE.
2. Live resolution + floor respected — resolves to Gemini 2.5 Pro (cheapest rung-≥THREE catalog model); no downgrade. Emits RouteSelected + RouteResolved (cost-aware, candidateCount > 1).
3. Unsatisfiable floor → typed failure — a floor above the catalog (rung 5) throws RoutingFloorUnmetException + emits RouteFloorUnmet; the outbound client is never invoked.

./gradlew :ampere-core:jvmTest (new test + existing AgentDefinitionRungThreadingTest / SparkBasedAgentCodeFactoryTest), :ampere-core:compileCommonMainKotlinMetadata, and ktlintFormat pass.

Pre-existing, unrelated NPE failures in ModelDescriptorTest / ModelDescriptorRegistryRungTest (model-graph class-init reentrancy) exist on main and are out of scope here.

Out of scope

• Activating all agents — only CODE, by design.
• Consent/metering interplay — flagged for the metering epic, not solved here.

🤖 Generated with Claude Code

[github-actions]

Concept staleness check — 1 warning(s).

These changes touched files listed under a concept's tracked_sources without updating the concept file. Either update the concept (and bump last_verified) or include a Concept-Verified: <ConceptName> trailer in a commit on this PR.

Validator output

⚠ Concept 'CognitiveRelay' may be stale: ampere-core/src/commonMain/kotlin/link/socket/ampere/agents/domain/routing/CapabilityRoutingDefaults.kt matches tracked_sources pattern ampere-core/src/commonMain/kotlin/link/socket/ampere/agents/domain/routing/** but docs/concepts/cognitive-relay.md was not modified.

validate-concepts: 1 warning(s). Validator informs; never blocks.