Document measurement loop plan and ecosystem integration strategy.

Persist INTENT and ecosystem assessments in history/, add ADR-004 for
project metrics with Helix Forge correlation, and register WP-0003 and
WP-0004 workplans with State Hub. Update SCOPE, README, and agency-framework
docs to reflect the two-layer measurement model.

docs/agency-framework.md

@@ -234,8 +234,56 @@ All agents that do session-bound project work have `memory: enabled` in their fr
 
 ---
 
+## Project Metrics
+
+Project-scoped **quantitative** metrics complement qualitative memory (ADR-002).
+Per-execution records live under `.kaizen/metrics/<agent>/` and feed the
+kaizen optimizer loop.
+
+### Location
+
+```
+<project-root>/.kaizen/metrics/<agent-name>/
+  executions.jsonl
+  summary.json
+
+<project-root>/.kaizen/metrics/optimizer/
+  analysis.json
+  recommendations.jsonl
+```
+
+### CLI (WP-0003)
+
+```
+kaizen-agentic metrics record <agent>   # Append execution record at session close
+kaizen-agentic metrics show <agent>     # Summary + recent executions
+kaizen-agentic metrics list             # Agents with metrics in project
+kaizen-agentic metrics export <agent>   # Dump executions.jsonl
+kaizen-agentic metrics optimize [agent] # Run optimizer on project metrics
+```
+
+`memory brief` includes a `## Performance Summary` when metrics exist (WP-0003
+Part 4).
+
+### Fleet correlation
+
+Project metrics correlate with **Helix Forge** fleet session metrics in
+`agentic-resources` via optional `helix_session_uid` (ADR-004). See
+[wiki/EcosystemIntegration.md](../wiki/EcosystemIntegration.md).
+
+### Evidence retention
+
+Optimizer outputs may be published to `artifact-store` (WP-0004 Part 3).
+
+---
+
 ## Related Documents
 
-- [ADR-001: Workplan Convention](../workplans/kaizen-agentic-WP-0001-community-engagement.md) — how work items are structured
-- [ADR-002: Project Memory Convention](../workplans/kaizen-agentic-WP-0002-agency-framework.md) — memory file location, structure, and lifecycle
-- [WP-0002: Agency Framework](../workplans/kaizen-agentic-WP-0002-agency-framework.md) — full implementation workplan
+- [ADR-001: Workplan Convention](adr/ADR-001-workplan-convention.md)
+- [ADR-002: Project Memory Convention](adr/ADR-002-project-memory-convention.md)
+- [ADR-003: Protocols Artifact Convention](adr/ADR-003-protocols-artifact-convention.md)
+- [ADR-004: Project Metrics Convention](adr/ADR-004-project-metrics-convention.md)
+- [wiki/EcosystemIntegration.md](../wiki/EcosystemIntegration.md) — two-layer measurement model
+- [WP-0002: Agency Framework](../workplans/kaizen-agentic-WP-0002-agency-framework.md)
+- [WP-0003: Measurement Loop](../workplans/kaizen-agentic-WP-0003-measurement-loop.md)
+- [WP-0004: Ecosystem Integration](../workplans/kaizen-agentic-WP-0004-ecosystem-integration.md)