[FEATURE] VSCode: Read/unread indicator for conversations with new responses

Preflight Checklist

• [x] I've searched existing issues for duplicates
• [x] I've thought about whether this is broadly useful or specific to my use case

Problem Statement

In the VSCode extension, a conversation where Claude has responded but the user hasn't looked at it yet looks identical to an old conversation the user already reviewed. There's no visual distinction between "has unread responses" and "already seen."

The existing status icons (running, waiting for plan approval) are great for showing active state, but once a conversation completes, there's no way to tell if you've reviewed the output or not.

Proposed Solution

Add an unread indicator using a new color on the existing status circle. The colored circle pattern is already familiar to users (green for running, etc.), so adding a color for "has unread responses" would be consistent and immediately intuitive.

• Mark as unread when Claude produces responses the user hasn't viewed
• Mark as read when the user opens and views the conversation

Use Case Example

Before: User has 15 past conversations. Some have new responses from Claude, others were reviewed days ago. They all look the same — the user has to click through them one by one to find which have new output.

After: Conversations with unread responses show a distinct color on their status circle. The user immediately sees which ones need attention.

Alternative Solutions

• Gmail-style bold/unbold on the conversation title
• A dot badge or notification count
• The Desktop app previously had blue unread markers (#32628) — this would bring parity to VSCode

Priority

Medium — becomes more important as users accumulate conversations.

Feature Category

IDE Integration (VSCode extension)