Create dedicated documentation page on upgrade procedures

Our documentation should contain a dedicated page on our possible upgrade scenarios.

Upgrades of the platform can be done in multiple steps:

• Optional: Set reconciliationPaused to true for some or all of your products
• Update CRDs
• Update Operators
• Optional: Set reconciliationPaused to false

Then we also have the product updates

• Upgrade productVersion

There are a few extra things we should document or take into consideration:

• Extra steps/caution needed when using custom images
• Document that (and why) pods will restart after an operator upgrade
• Document the fact that Helm can't manage CRDs: https://helm.sh/docs/chart_best_practices/custom_resource_definitions/
• Document OpenShift upgrade procedure
• Hint at platform release notes
• Hint at always having to check the release notes of the underlying products

首先在 Antora 仓库中找到现有的升级和发行说明文档，然后查看 issue 中描述的平台、产品、CRD、operator、Helm 和 OpenShift 操作流程。添加一个专门的页面，涵盖升级顺序、可选的 reconciliation 暂停、自定义镜像、pod 重启、CRD 限制以及相关发行说明。完成的标准是：列出的每个场景和注意事项都在一个易于发现的页面中得到清晰记录。