feat: inject thread progress into agent prompt (#127)

Agents now receive a Thread Progress section showing current step number
and role visit count, eliminating tool calls to count turns.

- util-agent: new buildThreadProgress() helper
- agent-hermes: inject before continuation/first-visit prompt
- agent-claude-code: same injection point

Fixes #127

packages/agent-hermes/src/hermes.ts

@@ -6,6 +6,7 @@ import {
   type AgentRunResult,
   buildContinuationPrompt,
   buildRolePrompt,
+  buildThreadProgress,
   createAgent,
 } from "@united-workforce/util-agent";
 import type { AcpUsage } from "./acp-client.js";
@@ -60,6 +61,9 @@ export function buildHermesPrompt(ctx: AgentContext): string {
     parts.push(ctx.outputFormatInstruction, "");
   }
 
+  // Inject thread progress so the agent knows step count and role visit count
+  parts.push(buildThreadProgress(ctx.steps, ctx.role), "");
+
   if (!ctx.isFirstVisit) {
     // Re-entry: show only steps since last visit, meta only
     parts.push(buildContinuationPrompt(ctx.steps, ctx.role, ctx.edgePrompt));