feat(vscode): animate tool call previews

[Drixled]

What

Add consistent accordion-style open and close motion to VS Code tool-call and reasoning details.

Why

Tool previews polished in #11146 still expanded abruptly and inconsistently. The new grid-track motion follows asynchronously rendered Markdown, highlighting, and diffs without animating to a stale measured height, retains deferred details only through collapse, preserves full-width output surfaces, and respects reduced-motion preferences. It avoids the JavaScript auto-height path that caused the shell rendering regression fixed in #11402.

Supersedes #11486, which GitHub closed when its branch was renamed.

[kilo-code-bot]

Code Review Summary

Status: 2 Issues Found | Recommendation: Address before merge

Overview

Severity	Count
CRITICAL	0
WARNING	2
SUGGESTION	0

Issue Details (click to expand)

WARNING

File	Line	Issue
packages/kilo-ui/src/components/basic-tool.css	457	The reduced-motion override is less specific than the new animation rules, so tool previews still animate at full speed.
packages/kilo-ui/src/components/message-part.css	741	The reduced-motion override is less specific than the new animation rules, so reasoning cards still animate at full speed.

Files Reviewed (6 files)

• .changeset/animate-tool-card-reveals.md
• packages/kilo-ui/src/components/basic-tool.css - 1 issue
• packages/kilo-ui/src/components/basic-tool.tsx
• packages/kilo-ui/src/components/message-part.css - 1 issue
• packages/kilo-ui/src/components/message-part.tsx
• packages/ui/src/components/basic-tool.tsx

Fix these issues in Kilo Cloud

Previous Review Summary (commit f92ad06)

Current summary above is authoritative. Previous snapshots are kept for context only.

Previous review (commit f92ad06)

Status: 2 Issues Found | Recommendation: Address before merge

Overview

Severity	Count
CRITICAL	0
WARNING	2
SUGGESTION	0

Issue Details (click to expand)

WARNING

File	Line	Issue
packages/kilo-ui/src/components/basic-tool.css	457	The reduced-motion override is less specific than the new animation rules, so tool previews still animate at full speed.
packages/kilo-ui/src/components/message-part.css	741	The reduced-motion override is less specific than the new animation rules, so reasoning cards still animate at full speed.

Files Reviewed (6 files)

• .changeset/animate-tool-card-reveals.md
• packages/kilo-ui/src/components/basic-tool.css - 1 issue
• packages/kilo-ui/src/components/basic-tool.tsx
• packages/kilo-ui/src/components/message-part.css - 1 issue
• packages/kilo-ui/src/components/message-part.tsx
• packages/ui/src/components/basic-tool.tsx

Fix these issues in Kilo Cloud

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_{Reviewed by gpt-5.4-20260305 · Input: 49.6K · Output: 4.5K · Cached: 77.2K}

_{Review guidance: REVIEW.md from base branch main}