fix(session-export): preserve streamed browser downloads

packages/session-query/session-export/tests/invariant.client.spec.ts

@@ -0,0 +1,16 @@
+import { describe, expect, it, vi } from 'vitest'
+import { Context } from '@deepseek-ai/cordis'
+import { apply, inject, name } from '../src/invariant.ts'
+
+describe('@deepseek-ai/dsh-session-export/invariant', () => {
+  it('registers the package-owned empty companion', async () => {
+    const register = vi.fn(() => vi.fn())
+    const ctx = new Context()
+    ctx.provide('invariants', { register })
+    const dispose = await apply(ctx)
+    expect(name).toBe('session-export-invariant')
+    expect(inject).toEqual(['invariants'])
+    expect(register).toHaveBeenCalledWith('@deepseek-ai/dsh-session-export', expect.any(Function))
+    dispose()
+  })
+})