#### What type of PR is this?
/area core
/kind improvement
/milestone 2.4.0
#### What this PR does / why we need it:
将系统设置中的用户注册的默认角色输入框改为选择框。
<img width="575" alt="image" src="https://user-images.githubusercontent.com/21301288/228888394-8355b71e-7d18-46bf-b177-569fa7b311d6.png">
#### Special notes for your reviewer:
测试 `系统设置 -> 用户设置` 中的默认角色是否可以正常设置即可。
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind improvement
/area core
/milestone 2.4.0
#### What this PR does / why we need it:
当用户被删除时关联删除用户的绑定账号信息
how to test it?
1. 创建用户
2. 绑定账号
3. 使用管理员删除此用户并查看关联的 UserConnection 是否被删除
```shell
curl -u 'your-username:your-password' http://127.0.0.1:8090/apis/auth.halo.run/v1alpha1/userconnections | jq -r '.'
```
#### Which issue(s) this PR fixes:
Fixes#3639
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind feature
/area core
/area console
/milestone 2.4.0
#### What this PR does / why we need it:
新增用户注册功能
#### Which issue(s) this PR fixes:
Fixes#2813
#### Special notes for your reviewer:
#### Does this PR introduce a user-facing change?
```release-note
新增用户注册功能
```
#### What type of PR is this?
/kind feature
/area core
/milestone 2.4.x
#### What this PR does / why we need it:
修复 Local 认证方式的开关初始化状态为关闭
#### Which issue(s) this PR fixes:
Fixes#3602
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind feature
/milestone 2.4.x
/area core
#### What this PR does / why we need it:
提供 ReactiveSettingFetcher 供插件获取配置
此 PR 基于原有的阻塞的 SettingFetcher 逻辑挪到 DefaultReactiveSettingFetcher 中并将阻塞的实现用 Reactive 得代理，不需要测试，单元测试过了即可。
可以尝试在插件中依赖注入 ReactiveSettingFetcher 看是否能正确注入
#### Which issue(s) this PR fixes:
Fixes#3620
#### Does this PR introduce a user-facing change?
```release-note
提供 ReactiveSettingFetcher 供插件获取配置
```
#### What type of PR is this?
/kind improvement
/area core
/milestone 2.4.x
#### What this PR does / why we need it:
修复升级主题或插件时新增加的配置默认值没有更新的问题
how to test it?
1. 安装包含设置的主题后获取主题的 ConfigMap 并记下
2. 修改（增加/更新）主题的设置（Setting）的默认值，模拟更新主题
3. 期望默认值改变不会影响到之前已有的配置，对于新增加的配置的默认值会被合并到已有的 ConfigMap 中
#### Which issue(s) this PR fixes:
Fixes#3446
#### Does this PR introduce a user-facing change?
```release-note
修复升级主题或插件时新增加的配置默认值没有更新的问题
```
#### What type of PR is this?
/kind feature
/area core
#### What this PR does / why we need it:
This PR provides a configuration item to control referrer-policy header. Default is `strict-origin-when-cross-origin`.
```yaml
halo:
security:
referrer-options:
policy: no-referrer
```
#### Which issue(s) this PR fixes:
Fixes https://github.com/halo-dev/halo/issues/3064
#### Does this PR introduce a user-facing change?
```release-note
提供配置以控制站点引用策略（Referrer-Policy）
```
#### What type of PR is this?
/kind bug
/area core
#### What this PR does / why we need it:
This PR makes extension initialization before starting reconcilers to prevent modification conflicts.
#### Which issue(s) this PR fixes:
Fixes https://github.com/halo-dev/halo/issues/3601
#### Special notes for your reviewer:
1. Try to run Halo 2.3.2 with command `docker run --rm -it -v ~/halo2-dev:/root/.halo2 -p 8090:8090 halohub/halo:2.3.2`
2. Then run Halo 2.4.0-SNAPSHOT with dev profile.
```bash
./gradlew bootRun --args="--spring.profiles.active=dev"
```
4. Check logs and logging functionality
5. Repeat steps above
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind improvement
#### What this PR does / why we need it:
升级默认主题的版本为 1.2.1：https://github.com/halo-dev/theme-earth/releases/tag/v1.2.1
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind feature
/milestone 2.4.x
/area core
#### What this PR does / why we need it:
支持聚合多个角色到一个角色
see #3560 for more details.
how to test it?
创建一个测试角色和和一个 RoleBinding 将此角色的绑定到其他角色，在不修改用户权限的情况下，用户将拥有新创建的测试角色的权限。
#### Which issue(s) this PR fixes:
Fixes#3560
#### Does this PR introduce a user-facing change?
```release-note
支持聚合多个角色到一个角色
```
#### What type of PR is this?
/kind feature
/milestone 2.4.x
/area core
#### What this PR does / why we need it:
提供 Secret 自定义模型用于存储敏感数据
例如：密码、token 等
参考自： https://kubernetes.io/docs/concepts/configuration/secret
#### Which issue(s) this PR fixes:
Fixes#3267
#### Does this PR introduce a user-facing change?
```release-note
提供 Secret 自定义模型用于存储敏感数据
```
#### What type of PR is this?
/kind improvement
/area core
/milestone 2.4.x
/kind api-change
#### What this PR does / why we need it:
修复未审核过的回复包含在了评论的回复数量中的问题
此改动需要评论组件修改回复数量取值为 `status.visibleReplyCount`
how to test it?
1. 创建评论，并在评论下回复
2. 评论的所有回复被计数在 `status.replyCount` 中
3. 而 `status.visibleReplyCount` 数量不包含 `spec.hiden=true` 或 `spec.approved = false` 的
#### Which issue(s) this PR fixes:
Fixes#3165
#### Does this PR introduce a user-facing change?
```release-note
修复未审核过的回复包含在了评论的回复数量中的问题
```
#### What type of PR is this?
/kind improvement
/area console
#### What this PR does / why we need it:
隐藏个人资料中未启用的认证方式。
#### Which issue(s) this PR fixes:
Fixes#3556
#### Special notes for your reviewer:
测试方式：
1. 安装 OAuth 2 插件：https://github.com/halo-sigs/plugin-oauth2/pull/3
2. 再不做任何配置的情况下，访问已登录用户的个人资料页面，检查是否列出了认证方式。
3. 配置某个认证方式并开启，再检查是否列出了已启用的认证方式。
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind improvement
/area core
/milestone 2.4.x
#### What this PR does / why we need it:
修复插件启动失败后停止插件时出现的 NPE 问题
how to test it?
见 #3579，先使用 issue 描述步骤复现问题，在切换到此 PR 尝试相同步骤
#### Which issue(s) this PR fixes:
Fixes#3579
#### Does this PR introduce a user-facing change?
```release-note
修复插件启动失败后停止插件时出现的 NPE 问题
```
#### What type of PR is this?
/kind cleanup
/area core
#### What this PR does / why we need it:
This PR totally refactor project structure for a better plugin development. Now we can maintain and publish api and platform modules at Halo application side, which will be references by plugins.
Currently, we can execute command `./gradlew clean publish` to publish api and platform modules into **local** Maven repository, so that we can refer these dependencies (`run.halo.tools.platform:plugin:2.4.0-SNAPSHOT` and `run.halo.app:api:2.4.0-SNAPSHOT`) in plugin projects.
I will make another pull request to publish api library and platforms into Maven central repository.
**Modules explanation**:
- API module contains common classes which might be used by plugins.
- Plugin Platform module contains dependency declarations of other plugin API modules.
- Application Platform module contains dependency declarations application module might uses.
If we want to build application only(exclude check and jar), we have to execute the command below:
```bash
./gradlew clean :application:build -x :application:check -x :application:jar
```
The executable Jar will be generated at folder `application/build/libs/`.
If we want to build a Docker image, we could execute the command below:
```bash
docker build -t johnniang/halo:project-structure .
# Test the Docker image
docker run -it --rm -p8090:8090 johnniang/halo:project-structure
```
#### Which issue(s) this PR fixes:
Fixes https://github.com/halo-dev/halo/issues/2730
#### Special notes for your reviewer:
#### Does this PR introduce a user-facing change?
```release-note
重构项目结构
```
Ryan Wang
