docs(tui): changelog and design for clean activity rendering

Author: elkaix

CHANGELOG.md

@@ -15,6 +15,10 @@ GitHub Releases page; `0.8.0` is the new starting line.
 
 ## Unreleased
 
+- **Thinking and subagent activity now render cleanly in the terminal.** Live reasoning previews
+  render complete Markdown without exposing top-level HTML comments, activity-tree rows remain
+  visually stable, and the coral shimmer is reserved for the active verb spinner.
+
 ## 0.57.0 (2026-07-05)
 
 - **No more ghost/duplicate input prompt while the agent works.** After

docs/en/release-notes/changelog.md

@@ -17,6 +17,10 @@ GitHub Releases page; `0.8.0` is the new starting line.
 
 ## Unreleased
 
+- **Thinking and subagent activity now render cleanly in the terminal.** Live reasoning previews
+  render complete Markdown without exposing top-level HTML comments, activity-tree rows remain
+  visually stable, and the coral shimmer is reserved for the active verb spinner.
+
 ## 0.57.0 (2026-07-05)
 
 - **No more ghost/duplicate input prompt while the agent works.** After