wip: Affine Intelligent Switch Markdown View & Ephemeral Action View

[Lakr233]

Fixed plenty of bug and is now smooth to use.

• switch to home made markdown parser & render engine
• switch to home made message list view
• switch auto scroll to match xAI logic
• error when chating is now shown
• fixed view shifting problem in message list
• fixed menu not shown when selecting to translate
• fixed document content with ephemeral action
• fixed AI button progress indicator not shown
• added text selection in markdown view
• added ChidoriMenu as translate language selector

[graphite-app]

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