refactor(client): name the compile face in every client test filename

A test file under packages/client now says which face it covers:
`*.client.spec.{ts,tsx}` and its `*.client.{ts,tsx}` helpers belong to the
Client aggregate, `*.host.spec.ts` to the host aggregate. The carrier's four
node-half specs take the Host suffix.

The two suffixes are mutually exclusive, so each aggregate excludes the
other's and both keep one broad test glob: `exclude` wins over `include`, and
`packages/client/**` no longer has to be excluded wholesale from the host
program with per-file `files` entries carved back out of it. A Host-face spec
that reaches only Host source therefore needs no cross-face project
reference, which the split-project rule rejects.

vitest still discovers every file through `**/*.spec.{ts,tsx}`.

packages/client/ui-question/tests/browser-plugin.client.spec.ts

@@ -0,0 +1,74 @@
+/**
+ * apply wiring on a real cordis Context + SlotsService: QuestionComposer
+ * registered as the `question` entry of the conversation-declared composer
+ * slot with ZERO business face (data and verbs ride the dispatched carrier),
+ * declaration-aware activation, and fiber-teardown unregistration. Component and
+ * domain-face behavior is covered props-direct in question-composer.spec.tsx;
+ * no renderer machinery here.
+ */
+import { Context } from '@deepseek-ai/cordis'
+import { describe, expect, it } from 'vitest'
+import { SlotsService } from '@deepseek-ai/dsh-client-runtime/client'
+import { LocaleService } from '@deepseek-ai/dsh-client-locale/client'
+import { QuestionComposer } from '../src/client/QuestionComposer.tsx'
+import { apply, inject } from '../src/client/index.ts'
+
+async function bench() {
+  const ctx = new Context()
+  await ctx.plugin(SlotsService).await()
+  const slots = ctx.get('slots') as SlotsService
+  // The composer slot exists only while its declaring entry is live.
+  slots.register(
+    { name: 'root', children: { 'conversation.composer': { kind: 'chain', scope: 'session' } } } as never,
+    () => null,
+  )
+  ctx.provide('locale', new LocaleService(ctx))
+  return { ctx, slots }
+}
+
+describe('apply', () => {
+  it('declares the services it binds', () => {
+    expect(inject).toEqual(['slots', 'locale'])
+  })
+
+  it('waits until a live entry declares the composer slot', async () => {
+    const ctx = new Context()
+    await ctx.plugin(SlotsService).await()
+    ctx.provide('locale', new LocaleService(ctx))
+    const fiber = ctx.plugin({ inject: [...inject], apply })
+    await fiber.await()
+    expect(ctx.slots.entries('conversation.composer')).toHaveLength(0)
+    ctx.slots.register(
+      { name: 'root', children: { 'conversation.composer': { kind: 'chain', scope: 'session' } } } as never,
+      () => null,
+    )
+    await Promise.resolve()
+    expect(ctx.slots.entries('conversation.composer')).toHaveLength(1)
+  })
+
+  it('registers the question entry: routing selector, no inject face', async () => {
+    const { ctx, slots } = await bench()
+    await ctx.plugin({ inject: [...inject], apply }).await()
+    const entry = slots.entries('conversation.composer')[0]!
+    expect(entry.component).toBe(QuestionComposer)
+    // The whole behavior surface rides the matched carrier: no business face;
+    // copy rides the standard locale seat.
+    expect(entry.inject).toBeUndefined()
+    expect(entry.locale).toBe('question')
+    // The selector narrows the chain currency: question wait in → that wait; none → null.
+    const select = entry.select as (owner: { interactions: readonly { kind: string }[] }) => unknown
+    const question = { kind: 'question' }
+    expect(select({ interactions: [{ kind: 'approval' }, question] })).toBe(question)
+    expect(select({ interactions: [{ kind: 'approval' }] })).toBeNull()
+    expect(select({ interactions: [] })).toBeNull()
+  })
+
+  it('teardown unregisters the slot entry', async () => {
+    const { ctx, slots } = await bench()
+    const fiber = ctx.plugin({ inject: [...inject], apply })
+    await fiber.await()
+    expect(slots.entries('conversation.composer')).toHaveLength(1)
+    await fiber.dispose()
+    expect(slots.entries('conversation.composer')).toHaveLength(0)
+  })
+})