docs: 交付文档、维护指引与端到端回归

补齐 README、开发计划、维护交接与 E2E 用例，执行最终验收。

e2e/specs/widget/chat-styles.spec.ts

@@ -0,0 +1,58 @@
+import { test, expect, AI_REPLY, customizeAgent, findPerson } from '@e2e'
+
+// Each way a visitor reaches the chat, and each again when the first answer that
+// binds them to a customer goes missing (the socket then gets the page's anonymous
+// token and the widget has to authorize again).
+for (const lost of [false, true]) {
+  const when = lost ? ', even when its first authorization goes missing' : ''
+
+  test.describe(`chat styles${lost ? ' (first authorization lost)' : ''}`, () => {
+    test.beforeEach(async ({ widget }) => {
+      if (lost) await widget.loseFirstAuthorization()
+    })
+
+    test(`an email-first agent: the visitor gives an email and gets the answer${when} @widget`, async ({ agent, widget, llm, adminApi }) => {
+      await customizeAgent(adminApi, agent.id, { collect_email: true })
+      await llm.script(agent, (s) => s.otherwise().reply('Thanks, how can I help?'))
+
+      await widget.embed()
+      await widget.openToEmailGate()
+      await widget.giveEmail()
+      await widget.send('Hello')
+
+      await expect(widget.lastAgentMessage()).toHaveText('Thanks, how can I help?', AI_REPLY)
+      expect((await findPerson(adminApi, widget.customer.email)).email).toBe(widget.customer.email)
+    })
+
+    test(`an Ask anything agent answers in its panel, with no email asked${when} @widget`, async ({ agent, widget, llm, adminApi }) => {
+      await customizeAgent(adminApi, agent.id, { chat_style: 'ASK_ANYTHING' })
+      await llm.script(agent, (s) => s.otherwise().reply('We ship worldwide.'))
+
+      await widget.embed()
+      await widget.openAskAnything()
+      await widget.ask('Do you ship abroad?')
+
+      await expect(widget.lastAnswer()).toHaveText('We ship worldwide.', AI_REPLY)
+    })
+
+    test.describe('lead capture', () => {
+      test.use({ agentSettings: { leadCapture: true } })
+
+      test(`a visitor with no email asked shares details and becomes a lead${when} @widget @leads`, async ({ agent, widget, llm, adminApi }) => {
+        const { email, name } = widget.customer
+        await llm.script(agent, (s) => s
+          .when(/@/).captureLead('Thanks! Someone from sales will reach out.', { email, name })
+          .otherwise().reply('Happy to help — what is your email?'))
+
+        await widget.embed()
+        await widget.open()
+        await widget.send('I want a demo')
+        await expect(widget.lastAgentMessage()).toHaveText('Happy to help — what is your email?', AI_REPLY)
+        await widget.send(`I am ${name}, ${email}`)
+        await expect(widget.lastAgentMessage()).toHaveText('Thanks! Someone from sales will reach out.', AI_REPLY)
+
+        expect((await findPerson(adminApi, email)).lead_stage).toBe('lead')
+      })
+    })
+  })
+}