feat(examples): configure max-token success via env

examples/jsonrpc-agent/README.md

@@ -18,6 +18,7 @@ The surrounding runtime also loads JSONL session persistence and automatic conte
 | `DEEPSEEK_API_KEY` | Credential passed to the OpenAI-compatible host endpoint |
 | `DEEPSEEK_BASE_URL` | Host endpoint used by `dsh-llm-deepseek` |
 | `DSH_CWD` | Agent workspace for bash and filesystem tools |
+| `DSH_MAX_TOKENS_AS_SUCCESS` | `true` (default) accepts token-limited results; `false` reports them as errors |
 | `DSH_SESSION_ROOT` | JSONL trajectory directory |
 | `DSH_SYSTEM_PROMPT` | Deployment-provided coding persona |