legacy 入站可升级为命名入站

顶层端口字段没有 proxy 可写（listener/inbound/base.go:97），界面上
切不了订阅。升级删掉顶层键、建同端口的 listener：listen 按 allow-lan
推导后写死，全局规则里 MATCH 之前的部分复制成附加规则，来源照抄
MATCH 目标组的 use:，让流量去向尽量不变。udp 不写，命名入站解析时
默认就是开的（listener/parse.go:52）。
「默认」tag 随术语表改成 legacy，旧叫法进 avoid 列表。

shared/inbound-groups.test.ts

@@ -15,6 +15,7 @@ import {
   proxyGroupName,
   pruneGenerated,
   readSetup,
+  upgradeLegacyInbound,
 } from './inbound-groups.ts'
 import type { OutboundSetup } from './inbound-groups.ts'
 import { collectInbounds } from './inbounds.ts'
@@ -427,3 +428,73 @@ describe('附加规则', () => {
     expect((pruneGenerated(data)['sub-rules'] as ConfigObject).mine).toBeDefined()
   })
 })
+
+describe('legacy 入站升级', () => {
+  /** 形状仿照目标机器：一个 legacy 混合端口，全局规则是内网直连加 MATCH 兜底。 */
+  function legacyBase(): ConfigObject {
+    return {
+      'mixed-port': 7890,
+      'allow-lan': true,
+      'proxy-providers': {
+        subs: { type: 'http', url: URL, path: './providers/subs.yaml' },
+        other: { type: 'http', url: `${URL}2`, path: './providers/other.yaml' },
+      },
+      'proxy-groups': [{ name: 'PROXY', type: 'select', proxies: ['DIRECT'], use: ['subs'] }],
+      rules: [
+        'IP-CIDR,192.168.0.0/16,DIRECT,no-resolve',
+        'MATCH,PROXY',
+        'DOMAIN,dead.example,DIRECT',
+      ],
+    }
+  }
+  const legacyInbound = (data: ConfigObject) => collectInbounds(data).find((i) => i.isDefault)!
+
+  it('删掉顶层键，建同端口的命名入站，listen 按 allow-lan 推导写死', () => {
+    const data = legacyBase()
+    const next = upgradeLegacyInbound(data, legacyInbound(data))!
+    expect(next['mixed-port']).toBeUndefined()
+    expect((next.listeners as ConfigObject[]).at(-1)).toMatchObject({
+      name: 'mixed-port',
+      type: 'mixed',
+      port: 7890,
+      listen: '0.0.0.0',
+    })
+  })
+
+  it('allow-lan 关着时 listen 写 127.0.0.1', () => {
+    const data = { ...legacyBase(), 'allow-lan': false }
+    const next = upgradeLegacyInbound(data, legacyInbound(data))!
+    expect(((next.listeners as ConfigObject[]).at(-1) as ConfigObject).listen).toBe('127.0.0.1')
+  })
+
+  it('全局规则里第一条 MATCH 之前的部分复制成附加规则，全局规则原文不动', () => {
+    const data = legacyBase()
+    const next = upgradeLegacyInbound(data, legacyInbound(data))!
+    expect(readSubRules(next, 'mixed-port')).toEqual(['IP-CIDR,192.168.0.0/16,DIRECT,no-resolve'])
+    expect(next.rules).toEqual(legacyBase().rules)
+  })
+
+  it('升级完就在专属组模式下，来源照抄 MATCH 目标组的 use', () => {
+    const data = legacyBase()
+    const next = upgradeLegacyInbound(data, legacyInbound(data))!
+    expect(readSetup(next, 'mixed-port')).toEqual({
+      proxy: { sources: ['subs'], filter: null },
+      chain: null,
+    })
+    expect(managedWiring(next, collectInbounds(next).find((i) => i.name === 'mixed-port')!)).toBe(
+      true,
+    )
+  })
+
+  it('MATCH 目标组没有 use 时退回全部订阅', () => {
+    const data = legacyBase()
+    ;(data['proxy-groups'] as ConfigObject[])[0] = { name: 'PROXY', type: 'select', proxies: ['DIRECT'] }
+    const next = upgradeLegacyInbound(data, legacyInbound(data))!
+    expect(readSetup(next, 'mixed-port')?.proxy.sources).toEqual(['subs', 'other'])
+  })
+
+  it('已有同名入站时返回 null，不写出重名的 listener', () => {
+    const data = { ...legacyBase(), listeners: [{ name: 'mixed-port', type: 'mixed', port: 1 }] }
+    expect(upgradeLegacyInbound(data, legacyInbound(data))).toBeNull()
+  })
+})