feat: disable wechat payment channel, keep alipay only

- Remove wechat from provider options
- Set alipay as default payment channel
- Only alipay is currently enabled for unipay

wwwroot/recharge.ui

@@ -4,23 +4,19 @@
 		"width": "100%",
 		"height": "100%",
 		"fields":[
-			{
-				"name":"provider",
-				"uitype":"code",
-				"required":true,
-				"defautvalue":"wechat",
-				"label":"充值渠道",
-				"data":[
-					{
-						"value":"wechat",
-						"text":"微信支付"
-					},
-					{
-						"value":"alipay",
-						"text":"支付宝"
-					}
-				]
-			},
+		{
+			"name":"provider",
+			"uitype":"code",
+			"required":true,
+			"defaultvalue":"alipay",
+			"label":"充值渠道",
+			"data":[
+				{
+					"value":"alipay",
+					"text":"支付宝"
+				}
+			]
+		},
 			{
 				"name":"amount",
 				"label":"充值金额",