test(docs): P2 optimization - add router tests and update README

- Add router package tests to improve coverage
- Update README status date to 2026-05-29
- Mark all P0/P1 review blockers as resolved
- Update project readiness rating to B (conditional ready)

internal/api/router/router_test.go

@@ -0,0 +1,57 @@
+package router
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/user-management-system/internal/api/handler"
+)
+
+// TestRouter_NewRouter 测试 router 创建
+func TestRouter_NewRouter(t *testing.T) {
+	// 创建不带 avatar handler 的 router
+	router1 := NewRouter(
+		nil, nil, nil, nil, nil, nil,
+		nil, nil, nil, nil, nil, nil,
+		nil, nil, nil, nil, nil, nil,
+		nil, nil, nil, nil,
+	)
+	assert.NotNil(t, router1)
+	assert.Nil(t, router1.avatarHandler)
+
+	// 创建带 avatar handler 的 router
+	avatarHandler := &handler.AvatarHandler{}
+	router2 := NewRouter(
+		nil, nil, nil, nil, nil, nil,
+		nil, nil, nil, nil, nil, nil,
+		nil, nil, nil, nil, nil, nil,
+		nil, nil, nil, nil,
+		avatarHandler,
+	)
+	assert.NotNil(t, router2)
+	assert.NotNil(t, router2.avatarHandler)
+}
+
+// TestRouter_StructFields 测试 router 结构体字段
+func TestRouter_StructFields(t *testing.T) {
+	router := NewRouter(
+		nil, nil, nil, nil, nil, nil,
+		nil, nil, nil, nil, nil, nil,
+		nil, nil, nil, nil, nil, nil,
+		nil, nil, nil, nil,
+	)
+
+	// 验证所有字段都被正确设置（即使为 nil）
+	assert.NotNil(t, router.engine)
+	assert.Nil(t, router.authHandler)
+	assert.Nil(t, router.userHandler)
+	assert.Nil(t, router.roleHandler)
+	assert.Nil(t, router.permissionHandler)
+	assert.Nil(t, router.deviceHandler)
+	assert.Nil(t, router.logHandler)
+	assert.Nil(t, router.authMiddleware)
+	assert.Nil(t, router.rateLimitMiddleware)
+	assert.Nil(t, router.opLogMiddleware)
+	assert.Nil(t, router.ipFilterMiddleware)
+}