fix(uwf-hermes): read turn data from Hermes session file instead of ACP stream

Closes #519

The ACP protocol's tool_call updates only carry a display title (not a
structured tool name) and omit rawInput for polished tools, making the
reconstructed messages unusable for step read/show.

Changes:
- hermes.ts: storePromptResult reads ~/.hermes/sessions/session_{id}.json
  via loadHermesSession() instead of using ACP-reconstructed messages
- acp-client.ts: strip message/tool-call collection logic, keep only
  text chunk accumulation for final response extraction
- step.ts: TurnData gains role + toolCalls fields; formatTurnBody
  renders them in step read markdown output
- README: document sessions.write_json_snapshots requirement

packages/workflow-agent-hermes/README.md

@@ -18,6 +18,15 @@ bun add -g @uncaged/workflow-agent-hermes
 
 Requires the `hermes` CLI on `PATH`.
 
+Hermes must write session JSON snapshots so `uwf-hermes` can load structured tool calls from disk. Add this to `~/.hermes/config.yaml`:
+
+```yaml
+sessions:
+  write_json_snapshots: true
+```
+
+Session files are stored at `~/.hermes/sessions/session_{sessionId}.json`.
+
 ## CLI Usage
 
 Invoked by `uwf thread step` (not typically run directly):