cleanup(session): isolate trajectory inspection

packages/core/session/tests/surface.spec.ts

@@ -8,7 +8,6 @@ import {
   isSurfaceEvent,
 } from '@deepseek-ai/dsh-session'
 import { CallId } from '@deepseek-ai/dsh-llm'
-import { SurfaceManager } from '../src/surface.ts'
 
 /** Build a minimal session with turn boundaries and a single user message. */
 function surfaceSession(): Session {
@@ -190,19 +189,6 @@ describe('SurfaceManager', () => {
       { seq: 2, start: 0, end: 0, shadowedSeqs: [0] },
       { seq: 3, start: 2, end: 1, shadowedSeqs: [2, 1] },
     ])
-    expect(new SurfaceManager(s.events).contexts).toEqual([
-      { generation: 0, nodes: [0, 1] },
-      {
-        generation: 1,
-        nodes: [2, 1],
-        origin: { seq: 2, start: 0, end: 0, shadowedSeqs: [0] },
-      },
-      {
-        generation: 2,
-        nodes: [3],
-        origin: { seq: 3, start: 2, end: 1, shadowedSeqs: [2, 1] },
-      },
-    ])
     folded.nodes[0] = 99
     folded.replacements[0]!.shadowedSeqs.push(99)
     expect(s.surface.nodes).toEqual([3])
@@ -218,7 +204,6 @@ describe('SurfaceManager', () => {
     expect(s.surface.nodes).toEqual([1])
     const manager = s.surface as unknown as { _state: object }
     expect(Object.hasOwn(manager._state, 'replacements')).toBe(false)
-    expect(Object.hasOwn(manager, '_contexts')).toBe(false)
     expect(foldSurface(s.events).replacements).toEqual([
       { seq: 1, start: 0, end: 0, shadowedSeqs: [0] },
     ])