fix(员工代收款): 修正路由前缀注册方式，消除 /api/admin 根级 /:id 抢占

Register 的 basePath 仅用于生成 OpenAPI 文档，不参与路由注册；员工代收款
三个注册函数把资源前缀传给了 basePath、path 只写相对段，导致
GET /api/admin/:id 与 POST /api/admin/:id/close 落在 /api/admin 根上。
账单单段路径被当作路径 ID 解析返回“无效的路径ID”，并抢占其后注册的
同层单段 GET（/api/admin/refunds、/system-configs 等）。

改为 router.Group(前缀) 注册，与仓库既有写法一致；路由布局与文档路径不变。

internal/routes/employee_collection.go

@@ -23,10 +23,13 @@ func requireEmployeeCollectionConfigAccess(handler fiber.Handler) fiber.Handler
 }
 
 func registerEmployeeCollectionRoutes(router fiber.Router, handler *admin.EmployeeCollectionHandler, doc *openapi.Generator, basePath string) {
+	// 路由前缀必须交给 Group：Register 的 basePath 只用于生成 OpenAPI 文档，不参与路由注册，
+	// 否则相对路径会落到 /api/admin 根上并抢占同层后续路由。
+	group := router.Group("/employee-collection-payment-methods")
 	paymentMethodPath := basePath + "/employee-collection-payment-methods"
 	wrap := requireEmployeeCollectionConfigAccess
 
-	Register(router, doc, paymentMethodPath, "GET", "", handler.ListPaymentMethods, RouteSpec{
+	Register(group, doc, paymentMethodPath, "GET", "", handler.ListPaymentMethods, RouteSpec{
 		Summary:     "查询线下收款方式",
 		Description: "超级管理员可查询全部字典项；其他后台账号仅返回启用项，用于新核销申请选择收款方式。",
 		Tags:        []string{"员工代收款"},
@@ -34,7 +37,7 @@ func registerEmployeeCollectionRoutes(router fiber.Router, handler *admin.Employ
 		Output:      new(dto.EmployeeCollectionPaymentMethodListResponse),
 		Auth:        true,
 	})
-	Register(router, doc, paymentMethodPath, "POST", "", wrap(handler.CreatePaymentMethod), RouteSpec{
+	Register(group, doc, paymentMethodPath, "POST", "", wrap(handler.CreatePaymentMethod), RouteSpec{
 		Summary:     "创建线下收款方式",
 		Description: "仅超级管理员。稳定编码在未删除记录中唯一。",
 		Tags:        []string{"员工代收款"},
@@ -42,7 +45,7 @@ func registerEmployeeCollectionRoutes(router fiber.Router, handler *admin.Employ
 		Output:      new(dto.EmployeeCollectionPaymentMethodResponse),
 		Auth:        true,
 	})
-	Register(router, doc, paymentMethodPath, "PUT", "/:id", wrap(handler.UpdatePaymentMethod), RouteSpec{
+	Register(group, doc, paymentMethodPath, "PUT", "/:id", wrap(handler.UpdatePaymentMethod), RouteSpec{
 		Summary:     "更新线下收款方式",
 		Description: "仅超级管理员。可修改名称、排序、启停与备注；已被核销申请引用时不允许修改稳定编码。",
 		Tags:        []string{"员工代收款"},
@@ -51,7 +54,7 @@ func registerEmployeeCollectionRoutes(router fiber.Router, handler *admin.Employ
 		Output:      new(dto.EmployeeCollectionPaymentMethodResponse),
 		Auth:        true,
 	})
-	Register(router, doc, paymentMethodPath, "DELETE", "/:id", wrap(handler.DeletePaymentMethod), RouteSpec{
+	Register(group, doc, paymentMethodPath, "DELETE", "/:id", wrap(handler.DeletePaymentMethod), RouteSpec{
 		Summary:     "删除线下收款方式",
 		Description: "仅超级管理员。已被核销申请引用的字典项不可物理删除，只能停用。",
 		Tags:        []string{"员工代收款"},
@@ -64,10 +67,11 @@ func registerEmployeeCollectionRoutes(router fiber.Router, handler *admin.Employ
 // registerEmployeeCollectionBillRoutes 注册员工代收款账单查询、统计与关闭路由。
 // 账单可见性由应用层强制：欠款人仅见本人账单，超级管理员见全部。
 func registerEmployeeCollectionBillRoutes(router fiber.Router, handler *admin.EmployeeCollectionHandler, doc *openapi.Generator, basePath string) {
+	group := router.Group("/employee-collection-bills")
 	billPath := basePath + "/employee-collection-bills"
 	adminOnly := requireEmployeeCollectionConfigAccess
 
-	Register(router, doc, billPath, "GET", "", handler.ListBills, RouteSpec{
+	Register(group, doc, billPath, "GET", "", handler.ListBills, RouteSpec{
 		Summary:     "查询员工代收款账单",
 		Description: "欠款人仅返回本人欠款账单，超级管理员返回全部；支持来源、状态、时间、欠款人、客户筛选与分页。",
 		Tags:        []string{"员工代收款"},
@@ -76,7 +80,7 @@ func registerEmployeeCollectionBillRoutes(router fiber.Router, handler *admin.Em
 		Auth:        true,
 	})
 	// 统计必须先于 /:id 注册，保证路径按字面量优先匹配。
-	Register(router, doc, billPath, "GET", "/statistics", handler.StatisticsBills, RouteSpec{
+	Register(group, doc, billPath, "GET", "/statistics", handler.StatisticsBills, RouteSpec{
 		Summary:     "查询员工代收款账单统计",
 		Description: "与账单列表使用相同筛选条件与可见性范围，返回应收、已核销、未核销金额合计与待处理账单数；不接受分页参数。",
 		Tags:        []string{"员工代收款"},
@@ -84,7 +88,7 @@ func registerEmployeeCollectionBillRoutes(router fiber.Router, handler *admin.Em
 		Output:      new(dto.EmployeeCollectionBillStatisticsResponse),
 		Auth:        true,
 	})
-	Register(router, doc, billPath, "GET", "/:id", handler.GetBill, RouteSpec{
+	Register(group, doc, billPath, "GET", "/:id", handler.GetBill, RouteSpec{
 		Summary:     "查询员工代收款账单详情",
 		Description: "返回账单、来源退款冲销、分摊、核销申请与企业微信审批历史；附件只返回对象键引用。无权限与不存在返回同一错误。",
 		Tags:        []string{"员工代收款"},
@@ -92,7 +96,7 @@ func registerEmployeeCollectionBillRoutes(router fiber.Router, handler *admin.Em
 		Output:      new(dto.EmployeeCollectionBillDetailResponse),
 		Auth:        true,
 	})
-	Register(router, doc, billPath, "POST", "/:id/close", adminOnly(handler.CloseBill), RouteSpec{
+	Register(group, doc, billPath, "POST", "/:id/close", adminOnly(handler.CloseBill), RouteSpec{
 		Summary:     "关闭员工代收款账单",
 		Description: "仅超级管理员。仅允许关闭待核销或部分核销且不存在审批中分摊的账单；关闭只作废未核销余额并保留已核销金额。",
 		Tags:        []string{"员工代收款"},
@@ -106,9 +110,10 @@ func registerEmployeeCollectionBillRoutes(router fiber.Router, handler *admin.Em
 // registerEmployeeCollectionApplicationRoutes 注册核销申请的创建、重提与受控查询路由。
 // 可见性与代办权限由应用层强制：非超级管理员只能为本人账单操作，超级管理员代办必须填写原因。
 func registerEmployeeCollectionApplicationRoutes(router fiber.Router, handler *admin.EmployeeCollectionHandler, doc *openapi.Generator, basePath string) {
+	group := router.Group("/employee-collection-applications")
 	applicationPath := basePath + "/employee-collection-applications"
 
-	Register(router, doc, applicationPath, "POST", "", handler.CreateApplication, RouteSpec{
+	Register(group, doc, applicationPath, "POST", "", handler.CreateApplication, RouteSpec{
 		Summary:     "创建核销申请",
 		Description: "员工为本人可见账单创建；超级管理员可为账单欠款人代办且必须填写 acting_reason。服务端按账单可核销余额与付款金额校验分摊，任一失败不保存申请与预占。",
 		Tags:        []string{"员工代收款"},
@@ -116,7 +121,7 @@ func registerEmployeeCollectionApplicationRoutes(router fiber.Router, handler *a
 		Output:      new(dto.EmployeeCollectionApplicationSubmitResponse),
 		Auth:        true,
 	})
-	Register(router, doc, applicationPath, "GET", "", handler.ListApplications, RouteSpec{
+	Register(group, doc, applicationPath, "GET", "", handler.ListApplications, RouteSpec{
 		Summary:     "查询核销申请",
 		Description: "非超级管理员仅返回本人申请，超级管理员返回全部；支持状态、收款方式、申请人与创建时间筛选和分页。",
 		Tags:        []string{"员工代收款"},
@@ -124,7 +129,7 @@ func registerEmployeeCollectionApplicationRoutes(router fiber.Router, handler *a
 		Output:      new(dto.EmployeeCollectionApplicationListResponse),
 		Auth:        true,
 	})
-	Register(router, doc, applicationPath, "GET", "/:id", handler.GetApplication, RouteSpec{
+	Register(group, doc, applicationPath, "GET", "/:id", handler.GetApplication, RouteSpec{
 		Summary:     "查询核销申请详情",
 		Description: "返回申请事实、账单分摊与全部审批尝试历史；附件只返回对象键引用。无权限与不存在返回同一错误。",
 		Tags:        []string{"员工代收款"},
@@ -132,7 +137,7 @@ func registerEmployeeCollectionApplicationRoutes(router fiber.Router, handler *a
 		Output:      new(dto.EmployeeCollectionApplicationDetailResponse),
 		Auth:        true,
 	})
-	Register(router, doc, applicationPath, "PUT", "/:id", handler.ResubmitApplication, RouteSpec{
+	Register(group, doc, applicationPath, "PUT", "/:id", handler.ResubmitApplication, RouteSpec{
 		Summary:     "修改并重提核销申请",
 		Description: "仅申请人或被代办的超级管理员，且仅已驳回申请可修改；重提新增一条审批尝试记录与新的企业微信审批实例，历史材料不被覆盖。",
 		Tags:        []string{"员工代收款"},