feat: agent-claude-code reports real $usage from stream-json output

- Map parsed numTurns, inputTokens, outputTokens, durationMs to Usage type
- Add @united-workforce/protocol dependency + tsconfig reference
- 747 tests pass

Fixes #77
Refs #68

packages/agent-claude-code/package.json

@@ -23,6 +23,7 @@
   },
   "dependencies": {
     "@ocas/core": "^0.3.0",
+    "@united-workforce/protocol": "workspace:^",
     "@united-workforce/util": "workspace:^",
     "@united-workforce/util-agent": "workspace:^"
   },

packages/agent-claude-code/src/claude-code.ts

@@ -1,5 +1,6 @@
 import { spawn } from "node:child_process";
 import type { Store } from "@ocas/core";
+import type { Usage } from "@united-workforce/protocol";
 import { createLogger } from "@united-workforce/util";
 import {
   type AgentContext,
@@ -145,7 +146,14 @@ async function processClaudeOutput(
       );
     }
 
-    return { output, detailHash, sessionId, assembledPrompt, usage: null };
+    const usage: Usage = {
+      turns: parsed.numTurns,
+      inputTokens: parsed.usage.inputTokens,
+      outputTokens: parsed.usage.outputTokens,
+      duration: Math.round(parsed.durationMs / 1000),
+    };
+
+    return { output, detailHash, sessionId, assembledPrompt, usage };
   }
 
   // Truly unparseable output - provide enhanced error message

packages/agent-claude-code/tsconfig.json

@@ -2,5 +2,5 @@
   "extends": "../../tsconfig.json",
   "compilerOptions": { "rootDir": "src", "outDir": "dist" },
   "include": ["src"],
-  "references": [{ "path": "../util-agent" }]
+  "references": [{ "path": "../protocol" }, { "path": "../util-agent" }]
 }

pnpm-lock.yaml

@@ -63,6 +63,9 @@ importers:
       '@ocas/core':
         specifier: ^0.3.0
         version: 0.3.0
+      '@united-workforce/protocol':
+        specifier: workspace:^
+        version: link:../protocol
       '@united-workforce/util':
         specifier: workspace:^
         version: link:../util