refactor: snapshot attributes and post publish

[guqing]

What type of PR is this?

/kind improvement
/area core
/milestone 2.0

What this PR does / why we need it:

1. 简化 Snapshot 的职责，去除 Snapshot 中关于 version，publishTime 等与发布相关的东西，Snapshot本身没有发布概念
2. 对应修改文章和自定义页面，将版本的概念转移到拥有 Snapshot 的模型上，如 Post 和 SinglePage

⚠️此 PR 为破坏性更新，对旧数据不兼容，可能导致旧数据文章内容无法显示问题

Console 端需要做出一些修改：

• 将文章发布前调用保存内容的 API 修改为 /posts/{name}/content
• 将自定义页面发布前调用保存内容的 API 修改为 /singlepages/{name}/content

发布接口提供了一个 async 参数，默认值为 false此时发布API需要等待发布成功后才返回结果，如果等待超时则提示Publishing wait timeout., 如果传递 async=true 表示异步发布，更新完数据就成功，reconciler 在后台慢慢执行。

Special notes for your reviewer:

how to test it?

1. 新创建一篇文章，测试点击保存是否成功
2. 新创建一篇文章，测试编辑内容后直接发布是否成功
3. 测试发布过的文章的取消发布状态是否显示未发布状态
4. 对于 Snapshot，新建文章点保存会创建一个snapshot，点击发布则是更新之前点保存创建的一条，所以记录数不会多，发布之后进入编辑随便写点内容直接点发布后查询snapshot则会多一条记录。
5. 文章的 status 里的 conditions 最新添加的都在第一个即头插入，如果连续两次发布则不会在增加 condition，长度超过20条会把旧的 condition 删除掉
6. 自定义页面上同

/cc @halo-dev/sig-halo

Does this PR introduce a user-facing change?

Action Required: 简化 Snapshot 模型的职责，去除版本相关属性

[guqing]

/kind api-change

[ruibaby]

/lgtm

[ruibaby]

@guqing 需要处理一下冲突。

[JohnNiang]

实际测试时，可能会发生如下错误：

2022-11-18T16:29:12.193+08:00 ERROR 4940 --- [     parallel-7] a.w.r.e.AbstractErrorWebExceptionHandler : [87be3966-69]  500 Server Error for HTTP PUT "/apis/api.console.halo.run/v1alpha1/posts/0386ce9c-56fd-4cbb-9020-889010c51866/publish"

reactor.core.Exceptions$RetryExhaustedException: Retries exhausted: 10/10
	at reactor.core.Exceptions.retryExhausted(Exceptions.java:306) ~[reactor-core-3.5.0.jar:3.5.0]
	Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException: 
Assembly trace from producer [reactor.core.publisher.FluxConcatMapNoPrefetch] :
	reactor.core.publisher.Flux.concatMap(Flux.java:3877)
	reactor.util.retry.RetryBackoffSpec.lambda$generateCompanion$6(RetryBackoffSpec.java:545)
Error has been observed at the following site(s):
	*__________Flux.concatMap ⇢ at reactor.util.retry.RetryBackoffSpec.lambda$generateCompanion$6(RetryBackoffSpec.java:545)
	|_      Flux.contextWrite ⇢ at reactor.util.retry.RetryBackoffSpec.lambda$generateCompanion$6(RetryBackoffSpec.java:609)
	*____Flux.deferContextual ⇢ at reactor.util.retry.RetryBackoffSpec.generateCompanion(RetryBackoffSpec.java:543)
	*__________Mono.retryWhen ⇢ at run.halo.app.core.extension.endpoint.PostEndpoint.lambda$publishPost$16(PostEndpoint.java:200)
	*____________Mono.flatMap ⇢ at run.halo.app.core.extension.endpoint.PostEndpoint.publishPost(PostEndpoint.java:189)
	|_           Mono.flatMap ⇢ at run.halo.app.core.extension.endpoint.PostEndpoint.publishPost(PostEndpoint.java:203)
	|_               Mono.map ⇢ at org.springframework.web.reactive.function.server.support.HandlerFunctionAdapter.handle(HandlerFunctionAdapter.java:62)
	|_           Mono.flatMap ⇢ at org.springframework.web.reactive.DispatcherHandler.handleRequestWith(DispatcherHandler.java:184)
	*____________Mono.flatMap ⇢ at org.springframework.web.reactive.DispatcherHandler.handle(DispatcherHandler.java:154)
	*______________Mono.defer ⇢ at org.springframework.web.server.handler.DefaultWebFilterChain.filter(DefaultWebFilterChain.java:106)
	|_          Mono.doOnEach ⇢ at org.springframework.web.filter.reactive.ServerHttpObservationFilter.filter(ServerHttpObservationFilter.java:108)
	|_        Mono.doOnCancel ⇢ at org.springframework.web.filter.reactive.ServerHttpObservationFilter.filter(ServerHttpObservationFilter.java:118)
	|_      Mono.contextWrite ⇢ at org.springframework.web.filter.reactive.ServerHttpObservationFilter.filter(ServerHttpObservationFilter.java:122)
	*__Mono.transformDeferred ⇢ at org.springframework.web.filter.reactive.ServerHttpObservationFilter.filter(ServerHttpObservationFilter.java:101)
	|_             checkpoint ⇢ org.springframework.web.filter.reactive.ServerHttpObservationFilter [DefaultWebFilterChain]
	*______________Mono.defer ⇢ at org.springframework.web.server.handler.DefaultWebFilterChain.filter(DefaultWebFilterChain.java:106)

2022-11-18T16:34:26.993+08:00 ERROR 4940 --- [         task-2] reactor.core.publisher.Operators         : Operator called default onErrorDropped

reactor.core.Exceptions$ErrorCallbackNotImplemented: java.lang.IllegalArgumentException: value must not be null
Caused by: java.lang.IllegalArgumentException: value must not be null
	at org.apache.lucene.document.Field.<init>(Field.java:235) ~[lucene-core-9.4.1.jar:9.4.1 810817993e0956e63e29906e78a245949501b77d - ivera - 2022-10-20 15:29:24]
	Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException: 
Assembly trace from producer [reactor.core.publisher.MonoPeekFuseable] :
	reactor.core.publisher.Mono.doOnNext(Mono.java:2643)
	run.halo.app.search.post.PostEventListener.lambda$handlePostPublished$1(PostEventListener.java:36)
Error has been observed at the following site(s):
	*___Mono.doOnNext ⇢ at run.halo.app.search.post.PostEventListener.lambda$handlePostPublished$1(PostEventListener.java:36)
	*____Mono.flatMap ⇢ at run.halo.app.search.post.PostEventListener.handlePostPublished(PostEventListener.java:35)
	|_ Mono.doFinally ⇢ at run.halo.app.search.post.PostEventListener.handlePostPublished(PostEventListener.java:44)
Original Stack Trace:
		at org.apache.lucene.document.Field.<init>(Field.java:235) ~[lucene-core-9.4.1.jar:9.4.1 810817993e0956e63e29906e78a245949501b77d - ivera - 2022-10-20 15:29:24]
		at org.apache.lucene.document.StoredField.<init>(StoredField.java:116) ~[lucene-core-9.4.1.jar:9.4.1 810817993e0956e63e29906e78a245949501b77d - ivera - 2022-10-20 15:29:24]
		at run.halo.app.search.post.LucenePostSearchService.convert(LucenePostSearchService.java:157) ~[classes/:na]
		at run.halo.app.search.post.LucenePostSearchService.lambda$addDocuments$0(LucenePostSearchService.java:100) ~[classes/:na]
		at java.base/java.lang.Iterable.forEach(Iterable.java:75) ~[na:na]
		at run.halo.app.search.post.LucenePostSearchService.addDocuments(LucenePostSearchService.java:99) ~[classes/:na]
		at run.halo.app.search.post.PostEventListener.lambda$handlePostPublished$0(PostEventListener.java:38) ~[classes/:na]

测试步骤：

1. 创建一篇空的文章
2. 直接右上角发布按钮
3. 填写好标题、别名、分类和标签并点击发布按钮

[guqing]

实际测试时，可能会发生如下错误：

1. 第一个错误与 Reconiler 执行有关，调用 update 更新数据后触发 reconciler， 由于保存数据也是异步的，可能会导致 Reconciler 触发完成后 update sql 才被执行，这种情况下 reconciler 获取到旧数据无法发布，需要手动点击，可能需要关注 Reconciler 触发时机或者剔除机制,此错误不会导致数据丢失和无法发布
2. 第二个错误应该是旧数据可以重新创建环境重试，此 PR 是破坏性更新

[JohnNiang]

以上问题建议在下一个 PR 优化。

/approve

[f2c-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: JohnNiang

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• OWNERS [JohnNiang]

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[ruibaby]

/lgtm