Release fix: Truncation related fixes for mark as/jump to unread

[polqf]

🔗 Issue Links

🎯 Goal

Fix issues around Mark as/Jump to unread for scenarios around truncation

📝 Summary

There were some issues found when trying with truncated messages.

🛠 Implementation

• When checking if the last message was seen, we are now checking if it was seen or it is currently on screen
• Truncation events now clear the state for current user's read
• When discarding messages using the unread messages pill, we are resetting the state that determines if the channel was marked as unread in the current session

🎨 Showcase

Add relevant screenshots and/or videos/gifs to easily see what this PR changes, if applicable.

Before	After
img	img

🧪 Scenarios

** Truncation **

• Create a channel
• Add some messages with 2 users
• While in the channel, truncate it
• Receive new messages

Expected result:

• The unread message pill should not be displayed (It can be displayed as there is an issue on the backend)

** Mark as read when scrolled to bottom **

• Open a channel with quite some unread messages (We don't want the first one to be visible when opening)
• Scroll to the first unread
• Receive 2 messages
  • You should see in the scroll to bottom counter 2 new messages
• Scroll to bottom
  • 2 previous messages should be seen as read from the other device
• Receive new messages

Expected result:

• When receiving new messages, they should instantly be marked as read

** Do not mark as read when scrolled to top **

• Open a channel with quite some unread messages (We don't want the first one to be visible when opening)
• Scroll to the first unread
• Receive 2 messages
  • You should see in the scroll to bottom counter 2 new messages

Expected result:

• The 2 messages should not be seen as read from the other device

☑️ Contributor Checklist

• I have signed the Stream CLA (required)
• This change follows zero ⚠️ policy (required)
• This change should be manually QAed
• Changelog is updated with client-facing changes
• New code is covered by unit tests
• Comparison screenshots added for visual changes
• Affected documentation updated (docusaurus, tutorial, CMS)

🎁 Meme