docs(readme): 合规段第一条去掉防御腔 —— 平静陈述「用 Microsoft 账户登录」

- 英文：Microsoft sign-in only → Sign-in with your Microsoft account；删掉 There is no other
  account provider（过度否认本身是信号）
- 中文：只走 Microsoft 正版登录 → 用 Microsoft 账户登录；删掉「没有别家账户通道」，
  并避开「正版」这个词（中文圈里该词天然与「破解」对照，带防御姿态）
- 事实不变：device code → XBL → XSTS → api.minecraftservices.com，用玩家自己的账户与权益
- 第三条「联机游玩需要 Microsoft 账户与有效权益」保留独立一条（事实陈述，非否认）

README.md

@@ -12,9 +12,9 @@ attached to other agent tooling as an MCP server.
 
 ## Compliance statement
 
-- **Microsoft sign-in only.** Authentication is Microsoft OAuth 2.0 device code flow → Xbox Live →
-  XSTS → `api.minecraftservices.com`, using the player's own Microsoft account and their own game
-  entitlement. There is no other account provider.
+- **Sign-in with your Microsoft account.** Authentication goes through Microsoft OAuth 2.0
+  device code flow → Xbox Live → XSTS → `api.minecraftservices.com`, using the player's own
+  Microsoft account and their own game entitlement.
 - **Credentials stay on your machine.** Account tokens are stored locally only, are never sent to
   any server operated by this project, and the AI features cannot read them.
 - **Online play requires a Microsoft account and a valid game entitlement.**