Upgrade Instruction Page and New Blog Post

[iamshaynez]

因为在本地做的时候顺序乱了，所以在一条 PR 包含了下面两部分：

Instruction

• https://content.docs-68d.pages.dev/upgrade
• https://content.docs-68d.pages.dev/confluence-migration-instructions/

Blog Post

• https://content.docs-68d.pages.dev/blog/2024/02/25/2024/sequence-diagram-for-every-architect

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