docs: address graph review placement

examples/echo-agent/composition.md

@@ -0,0 +1,40 @@
+<!-- Generated by scripts/gen-doc-graphs.ts - do not edit by hand.
+     Run `pnpm run gen-doc-graphs` to regenerate. -->
+
+# Echo Agent App Composition
+
+The echo demo swaps in a local mock LLM and teaching echo tool, then loads the stdio app package for the shared spine and terminal front door.
+
+```mermaid
+flowchart LR
+  cfg["examples/echo-agent<br/>cordis.yml"]
+  plugin_echo_hmr["hmr<br/>@cordisjs/plugin-hmr"]
+  cfg --> plugin_echo_hmr
+  plugin_echo_mock_llm["mock-llm<br/>./src/mock-llm.ts"]
+  cfg --> plugin_echo_mock_llm
+  plugin_echo_echo_tool["echo-tool<br/>./src/echo-tool.ts"]
+  cfg --> plugin_echo_echo_tool
+  plugin_echo_bash["bash<br/>@deepseek-ai/dsh-bash-local"]
+  cfg --> plugin_echo_bash
+  plugin_echo_stdio_agent["stdio-agent<br/>@deepseek-ai/dsh-stdio-agent"]
+  cfg --> plugin_echo_stdio_agent
+  plugin_echo_stdio_agent --> bundle_agent_core["@deepseek-ai/dsh-agent-core"]
+  plugin_echo_stdio_agent --> bundle_jsonl["@deepseek-ai/dsh-session-persistence-jsonl"]
+  plugin_echo_stdio_agent --> frontdoor_stdio["readline UI<br/>console logger<br/>pre-created main agent"]
+  bundle_agent_core --> spine_llm["ctx.llm"]
+  bundle_agent_core --> spine_sessions["ctx.sessions"]
+  bundle_agent_core --> spine_tools["ctx.tools + tool-bash"]
+  bundle_agent_core --> spine_loop["ctx.agents + ctx.agentLoop"]
+```
+
+| Plugin id | Package / module |
+| --- | --- |
+| `hmr` | `@cordisjs/plugin-hmr` |
+| `mock-llm` | `./src/mock-llm.ts` |
+| `echo-tool` | `./src/echo-tool.ts` |
+| `bash` | `@deepseek-ai/dsh-bash-local` |
+| `stdio-agent` | `@deepseek-ai/dsh-stdio-agent` |
+
+Source config: [`examples/echo-agent/cordis.yml`](cordis.yml).
+
+Maintenance mode: hybrid: the leaf plugin list is parsed from its `cordis.yml`; app package expansion is curated from package source.