refactor agent pre-step inbox lifecycle

packages/session-persistence/session-checkpoint-policy/src/index.ts

@@ -8,7 +8,7 @@ import type { Context } from 'cordis'
 import type { Session } from '@deepseek-ai/dsh-session'
 import type { StreamChunk } from '@deepseek-ai/dsh-llm'
 import { TOOL_ABORTED_BEFORE_DISPATCH, type ToolExecutionResult } from '@deepseek-ai/dsh-tools'
-import type {} from '@deepseek-ai/dsh-agent'
+import type { PreStepDecision } from '@deepseek-ai/dsh-agent'
 import type {} from '@deepseek-ai/dsh-session-persistence'
 
 /** Cordis plugin name used by Loader diagnostics. */
@@ -76,5 +76,8 @@ export function apply(ctx: Context): void {
 
   // Before each request, persist everything committed by the preceding step;
   // the first step's call is an intentional no-op beyond any prompt intake.
-  ctx.on('agent/step', (agent): Promise<void> => ctx.sessions.flush(agent.session))
+  ctx.on('agent/pre-step', async (agent, _messages, _context, next): Promise<PreStepDecision> => {
+    await ctx.sessions.flush(agent.session)
+    return next()
+  })
 }