fix(pty-local): expect sessionId in resolved policy after merge-forward

Master's pty-local rewrite dropped the sessionId expectation from the
resolved-policy contract; sandbox-policy resolve() injects the owner
sessionId (sandbox branch design). Restore it in both expectations.

packages/pty/pty-local/tests/index.spec.ts

@@ -215,7 +215,7 @@ describe('LocalPtyBackend startup rollback', () => {
     expect(initialized).toHaveBeenCalledWith(undefined)
     expect((ctx.sandbox as RecordingSandbox).calls).toEqual([{
       argv: ['/bin/bash', '-i'],
-      policy: { mode: 'workspace-write', workspaceRoot: '/workspace' },
+      policy: { mode: 'workspace-write', sessionId: 'agent', workspaceRoot: '/workspace' },
     }])
   })
 
@@ -247,7 +247,7 @@ describe('LocalPtyBackend startup rollback', () => {
     })
     expect((ctx.sandbox as RecordingSandbox).calls).toEqual([{
       argv: ['/bin/bash', '-i'],
-      policy: { mode: 'workspace-write', workspaceRoot: '/session-workspace' },
+      policy: { mode: 'workspace-write', sessionId: 'agent', workspaceRoot: '/session-workspace' },
     }])
   })