fix: single page does not count visits (#2918)

#### What type of PR is this?
/kind bug
/area core

#### What this PR does / why we need it:
修复自定义页面没有统计访问量的问题
#### Which issue(s) this PR fixes:

Fixes #2912

#### Special notes for your reviewer:
how to test it?
创建自定义页面并到主题端访问，可以看到访问量增加

/cc @halo-dev/sig-halo 
#### Does this PR introduce a user-facing change?
```release-note
修复自定义页面没有统计访问量的问题
```

src/main/java/run/halo/app/theme/router/strategy/SinglePageRouteStrategy.java

@@ -42,6 +42,7 @@ public class SinglePageRouteStrategy implements DetailsPageRouteHandlerStrategy
         String name) {
         return request -> {
             Map<String, Object> model = new HashMap<>();
+            model.put("name", name);
             model.put("groupVersionKind", gvk);
             model.put("plural", getPlural());
             model.put(ModelConst.TEMPLATE_ID, DefaultTemplateEnum.SINGLE_PAGE.getValue());

src/test/java/run/halo/app/theme/router/strategy/SinglePageRouteStrategyTest.java

@@ -1,21 +1,30 @@
 package run.halo.app.theme.router.strategy;
 
+import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.lenient;
 import static org.mockito.Mockito.when;
 import static run.halo.app.theme.DefaultTemplateEnum.SINGLE_PAGE;
 
+import java.util.Map;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
+import org.springframework.http.MediaType;
 import org.springframework.test.web.reactive.server.WebTestClient;
 import org.springframework.web.reactive.function.server.RouterFunction;
 import org.springframework.web.reactive.function.server.ServerResponse;
+import org.springframework.web.server.ServerWebExchange;
 import reactor.core.publisher.Mono;
+import run.halo.app.core.extension.content.SinglePage;
+import run.halo.app.extension.GroupVersionKind;
+import run.halo.app.extension.Metadata;
 import run.halo.app.theme.finders.SinglePageFinder;
+import run.halo.app.theme.finders.vo.SinglePageVo;
+import run.halo.app.theme.router.ViewNameResolver;
 
 /**
  * Tests for {@link SinglePageRouteStrategy}.
@@ -28,9 +37,13 @@ class SinglePageRouteStrategyTest extends RouterStrategyTestSuite {
     @Mock
     private SinglePageFinder singlePageFinder;
 
+    @Mock
+    private ViewNameResolver viewNameResolver;
+
     @InjectMocks
     private SinglePageRouteStrategy strategy;
 
+
     @Override
     public void setUp() {
         lenient().when(viewResolver.resolveViewName(eq(SINGLE_PAGE.getValue()), any()))
@@ -82,6 +95,43 @@ class SinglePageRouteStrategyTest extends RouterStrategyTestSuite {
             .expectStatus().isOk();
     }
 
+    @Test
+    void ensureModel() {
+        // fix gh-2912
+        Metadata metadata = new Metadata();
+        metadata.setName("fake-name");
+        SinglePageVo singlePageVo = SinglePageVo.builder()
+            .metadata(metadata)
+            .spec(new SinglePage.SinglePageSpec())
+            .build();
+
+        when(singlePageFinder.getByName(eq("fake-name"))).thenReturn(Mono.just(singlePageVo));
+        permalinkHttpGetRouter.insert("/fake-slug",
+            strategy.getHandler(getThemeRouteRules(), "fake-name"));
+
+        when(viewNameResolver.resolveViewNameOrDefault(any(), any(), any()))
+            .thenReturn(Mono.just("page"));
+        when(viewResolver.resolveViewName(eq(SINGLE_PAGE.getValue()), any()))
+            .thenReturn(Mono.just(new EmptyView() {
+                @Override
+                public Mono<Void> render(Map<String, ?> model, MediaType contentType,
+                    ServerWebExchange exchange) {
+                    assertThat(model.get("name")).isEqualTo("fake-name");
+                    assertThat(model.get("plural")).isEqualTo("singlepages");
+                    assertThat(model.get("_templateId")).isEqualTo("page");
+                    assertThat(model.get("singlePage")).isEqualTo(singlePageVo);
+                    assertThat(model.get("groupVersionKind")).isEqualTo(
+                        GroupVersionKind.fromExtension(SinglePage.class));
+                    return Mono.empty();
+                }
+            }));
+        createClient().get()
+            .uri("/fake-slug")
+            .exchange()
+            .expectStatus().isOk()
+            .expectBody();
+    }
+
     WebTestClient createClient() {
         RouterFunction<ServerResponse> routeFunction = getRouterFunction();
         return getWebTestClient(routeFunction);