[kumo] add sidebar transition completion callbacks

[7michele7]

Adds completion callbacks for sidebar and collapsible open-state transitions.
Consumers can wait for layout to settle before measuring or scrolling content.

The callbacks follow the owned CSS transition. They fall back when animations are interrupted or disabled.

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• Reviews
  • bonk has reviewed the change
  • automated review not possible because: Bonk was explicitly excluded from this review
• Tests
  • Tests included/updated
  • Automated tests not possible - manual testing has been completed as follows:
  • Additional testing not necessary because:

Validation:

• pnpm --filter @cloudflare/kumo exec vp test run --project=unit src/components/sidebar/sidebar.test.tsx
• pnpm --filter @cloudflare/kumo exec vp test run --project=unit --no-file-parallelism
• pnpm --filter @cloudflare/kumo typecheck
• pnpm --filter @cloudflare/kumo lint
• pnpm --filter @cloudflare/kumo build

[pkg-pr-new]

npm i https://pkg.pr.new/@cloudflare/kumo@798

commit: 311145b

[github-actions]

Docs Preview

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Commit: 311145b

[github-actions]

📐 Bundle Size

Consumer fixtures bundled against packages/kumo/dist (peers external, minified ESM).

Fixture	Raw	Gzip	Brotli
Button (root)	174.6 KB	49.9 KB	43.1 KB
Button (components/button)	174.5 KB	49.9 KB	43.0 KB
Button + Dialog + Select (root)	299.5 KB	85.8 KB	71.8 KB
Button + Dialog + Select (component subpaths)	299.5 KB	85.9 KB	71.8 KB
Chart (root)	218.7 KB	63.4 KB	54.7 KB
Chart (components/chart)	218.6 KB	63.3 KB	54.7 KB
Badge (components/badge)	44.7 KB	11.7 KB	10.0 KB
Flow (components/flow)	208.9 KB	58.3 KB	50.5 KB
Button (primitives/button)	12.2 KB	4.4 KB	3.9 KB
Primitives barrel	635.8 KB	176.9 KB	139.3 KB
Code highlighting (code)	2.08 MB	467.9 KB	349.2 KB

npm tarball: 535 files, 1.47 MB packed, 6.85 MB unpacked.

⚠️ 22 flagged files in tarball (tests / raw scripts)

• dist/blocks-source/resource-list/resource-list.test.tsx
• scripts/component-registry/cache.ts
• scripts/component-registry/discovery.ts
• scripts/component-registry/example-cleanup.ts
• scripts/component-registry/index.test.ts
• scripts/component-registry/index.ts
• scripts/component-registry/markdown-generator.ts
• scripts/component-registry/metadata.ts
• scripts/component-registry/props-filter.ts
• scripts/component-registry/schema-generator.ts
• scripts/component-registry/sub-components.ts
• scripts/component-registry/types.ts
• scripts/component-registry/utils.ts
• scripts/component-registry/variant-parser.ts
• scripts/css-build.ts
• scripts/generate-primitives.ts
• scripts/theme-generator/config.ts
• scripts/theme-generator/generate-css.test.ts
• scripts/theme-generator/generate-css.ts
• scripts/theme-generator/index.ts
• scripts/theme-generator/migrate.ts
• scripts/theme-generator/types.ts

Report-only: no size thresholds are enforced yet.

Commit: 311145b6

[github-actions]

Visual Regression Report — 32 changed, 13 unchanged

32 screenshot(s) with visual changes:

Button / Basic

408 px (0.46%) changed

Before	After	Diff

Button / Variant: Secondary

250 px (0.28%) changed

Before	After	Diff

Button / Variant: Secondary Destructive

1,122 px (1.27%) changed

Before	After	Diff

Button / Loading State

182 px (0.21%) changed

Before	After	Diff

Button / Disabled State

117 px (0.13%) changed

Before	After	Diff

Button / Link as Button

449 px (0.51%) changed

Before	After	Diff

Button / Disabled Link

0 px (0%) changed

Before	After	Diff

Dialog / Dialog With Actions

362 px (0.41%) changed

Before	After	Diff

Dialog / Dialog Basic

396 px (0.45%) changed

Before	After	Diff

Dialog / Dialog Sizes

2,949 px (3.33%) changed

Before	After	Diff

Dialog / Dialog Alert

480 px (0.54%) changed

Before	After	Diff

Dialog / Dialog Confirmation

855 px (0.97%) changed

Before	After	Diff

Dialog / Dialog With Select

500 px (0.56%) changed

Before	After	Diff

Dialog / Dialog With Combobox

383 px (0.43%) changed

Before	After	Diff

Dialog / Dialog With Dropdown

500 px (0.56%) changed

Before	After	Diff

Dialog (Open)

0 px (0%) changed

Before	After	Diff

Select / Select Basic

859 px (0.97%) changed

Before	After	Diff

Select / Select Sizes

3,122 px (1.92%) changed

Before	After	Diff

Select / Select Placement

3,530 px (2.44%) changed

Before	After	Diff

Select / Select Dynamic Placement

3,801 px (3.65%) changed

Before	After	Diff

Select / Select Without Label

91 px (0.1%) changed

Before	After	Diff

Select / Select With Description

1,932 px (1.86%) changed

Before	After	Diff

Select / Select With Error

1,730 px (1.66%) changed

Before	After	Diff

Select / Select Placeholder

1,282 px (1.45%) changed

Before	After	Diff

Select / Select Custom Rendering

1,257 px (1.42%) changed

Before	After	Diff

Select / Select Loading

2,360 px (1.34%) changed

Before	After	Diff

Select / Select Multiple

938 px (1.06%) changed

Before	After	Diff

Select / Select Complex

1,739 px (1.67%) changed

Before	After	Diff

Select / Select Grouped

970 px (1.1%) changed

Before	After	Diff

Select / Select Grouped With Disabled

1,534 px (1.73%) changed

Before	After	Diff

Select / Select Long List

1,918 px (1.84%) changed

Before	After	Diff

Select (Open)

0 px (0%) changed

Before	After	Diff

13 screenshot(s) unchanged

• Button / Variant: Primary
• Button / Variant: Ghost
• Button / Variant: Destructive
• Button / Variant: Outline
• Button / Sizes
• Button / With Icon
• Button / Icon Only
• Button / Title
• Button / Link with Tooltip
• Dialog / Custom Max Width
• Select / Select With Tooltip
• Select / Select Disabled Options
• Select / Select Disabled Items

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Generated by Kumo Visual Regression