review: the persona becomes the system-prompt plugin's deployment config

Review round 2 (tianyicui inline comments):

- dsh-system-prompt itself registers the harness:identity (-100) and
  deployment:persona (0) sections — they must survive a swapped loop
  plugin, so they leave dsh-agent-loop; the persona text is the plugin's
  own validated 'persona' config. The model/cwd variables STAY on the
  loop: runtime facts of the agents it drives.
- AgentOptions.systemPrompt is deleted with all its forwarding plumbing:
  the app configs' systemPrompt keys become 'persona' routed through
  dsh-agent-core (schema = z.intersect of the owners'), the ACP bridge
  and tool-subagent stop carrying persona configuration, and subagent
  children now render the deployment persona like every other agent.
- Example personas drop transport/interface trivia (ACP, CLI) — facts
  irrelevant to the model.
- Root CONTEXT.md removed (not idiomatic); its persona definition was
  wrong under the new ownership anyway.
- Docs, READMEs, the prompt-variables RFC, and generated catalogs
  updated; new loop test pins the assemble-waterfall escape valve
  (an emptied assembly sends NO system field).

packages/ui/acp-agent/README.md

@@ -23,7 +23,7 @@ Because the package wires no logger entry, an ACP leaf has **nothing to get wron
 | Key | Default | Routed to |
 |---|---|---|
 | `model` | (required) | the per-session agent template the bridge creates agents from |
-| `systemPrompt` | (required) | the per-session agent's persona template (may reference `{{model}}`/`{{cwd}}`) |
+| `persona` | — | the deployment persona template (may reference `{{model}}`/`{{cwd}}`), routed to `dsh-system-prompt` |
 | `persistenceRoot` | `./.sessions` | the JSONL backend's root directory |
 
 The leaf supplies the swappable backends: an LLM adapter (`llm-deepseek` for the real model, `llm-replay` for keyless snapshot replay) and a bash executor (`bash-local`).

packages/ui/acp-agent/src/index.ts

@@ -39,35 +39,38 @@ import SessionPersistenceJsonl from '@deepseek-ai/dsh-session-persistence-jsonl'
 export const name = 'acp-agent'
 
 /**
- * App config: the swappable per-deployment values. `model`/`systemPrompt`
- * configure the agent template the ACP bridge creates each session's agent from
- * (NOT a pre-created agent — ACP creates agents at `session/new`);
+ * App config: the swappable per-deployment values. `model` configures the
+ * agent template the ACP bridge creates each session's agent from (NOT a
+ * pre-created agent — ACP creates agents at `session/new`); `persona` is the
+ * deployment persona (forwarded to the system-prompt plugin);
  * `persistenceRoot` is the JSONL backend's directory.
  */
 export interface Config {
   /** Model name for ACP-created agents (must have a registered adapter). */
   model: string
-  /** Per-agent system prompt for ACP-created agents. */
-  systemPrompt: string
+  /** Deployment persona (the system-prompt plugin's `persona` config). */
+  persona?: string
   /** Directory the JSONL session backend writes under. Defaults to `./.sessions`. */
   persistenceRoot?: string
 }
 
 export const Config: z<Config> = z.object({
   model: z.string().required(),
-  systemPrompt: z.string().required(),
+  persona: z.string(),
   persistenceRoot: z.string().default('./.sessions'),
 })
 
 /**
  * Compose the spine with the ACP front door. The agent-core bundle pre-creates
- * NO agents (its `agents` list defaults to `[]`); the JSONL backend persists
- * under `persistenceRoot`; the ACP bridge owns stdout for JSON-RPC and creates
- * one agent per `session/new` from `model`/`systemPrompt`. No logger, no `hmr` —
- * stdout stays pure.
+ * NO agents (its `agents` list defaults to `[]`) and carries the deployment
+ * `persona`; the JSONL backend persists under `persistenceRoot`; the ACP
+ * bridge owns stdout for JSON-RPC and creates one agent per `session/new`
+ * from `model`. No logger, no `hmr` — stdout stays pure.
  */
 export function apply(ctx: Context, config: Config): void {
-  ctx.plugin(agentCore)
+  ctx.plugin(agentCore, {
+    ...config.persona !== undefined ? { persona: config.persona } : {},
+  })
   ctx.plugin(SessionPersistenceJsonl, { root: config.persistenceRoot ?? './.sessions' })
-  ctx.plugin(acp, { model: config.model, systemPrompt: config.systemPrompt })
+  ctx.plugin(acp, { model: config.model })
 }

packages/ui/acp-agent/tests/acp-agent.spec.ts

@@ -24,7 +24,7 @@ async function mount(config: acpAgent.Config): Promise<Context> {
 
 describe('dsh-acp-agent composition', () => {
   it('brings up the spine + persistence + the ACP bridge', async () => {
-    const ctx = await mount({ model: 'mock', systemPrompt: 'hi', persistenceRoot: '/tmp/dsh-acp-agent-test' })
+    const ctx = await mount({ model: 'mock', persona: 'hi', persistenceRoot: '/tmp/dsh-acp-agent-test' })
     expect(ctx.get('agents')).toBeDefined()
     expect(ctx.get('sessions')).toBeDefined()
     expect(ctx.get('sessionPersistence')).toBeDefined()
@@ -40,7 +40,8 @@ describe('dsh-acp-agent composition', () => {
     // `ctx.plugin`, which validates+defaults the config first) with no
     // persistenceRoot, so the runtime fallback is the one that fires.
     const ctx = new Context()
-    acpAgent.apply(ctx, { model: 'mock', systemPrompt: 'hi' })
+    // No persona: covers the omitted-persona forwarding branch too.
+    acpAgent.apply(ctx, { model: 'mock' })
     await new Promise(resolve => setTimeout(resolve, 50))
     expect(ctx.get('sessionPersistence')).toBeDefined()
     await ctx.fiber.dispose()