feat(shared): add UI primitives and kernel barrel

[rivodotlove]

What

Adds reusable, cva-based UI primitives under src/shared/ui with a barrel export:

• Box — block div with display variant + asChild
• Flex — flexbox div with direction/align/justify/wrap/gap/inline + asChild
• Typography — variant (h1–h4, p, span, code, muted, …) maps to semantic tag, as override + asChild
• Button, Checkbox, Label, Textarea — shadcn/radix primitives

Also adds a src/shared/kernel barrel re-exporting registry + result, and hardens main.tsx root lookup with an explicit HTMLElement cast.

Why

Establishes a small design-system layer so feature code composes primitives instead of repeating raw div/span + Tailwind. Consumer refactors (shell, base64) land in follow-up PRs.

Verification

vp check passes (format, lint, types) on all new files.

🤖 Generated with Claude Code

Summary by CodeRabbit

Release Notes

• New Features

  • Added comprehensive UI component library with Box, Button, Checkbox, Flex, Label, Textarea, and Typography components featuring configurable display and styling variants.

• Refactor

  • Updated root initialization and reorganized module export structure.

[coderabbitai]

Caution

Review failed

Pull request was closed or merged during review

📝 Walkthrough

Walkthrough

This PR establishes core shared library infrastructure by introducing a comprehensive UI component library, configuring kernel module exports, and refactoring the application entry point. The UI components follow a consistent pattern: define variants via class-variance-authority, render polymorphically with Radix UI, and apply merged styling.

Changes

Shared Library and Application Foundation

Layer / File(s)	Summary
Application entry point root element resolution src/main.tsx	DOM root element is resolved into a typed variable before being passed to createRoot, removing the inline non-null assertion.
Kernel module public surface src/shared/kernel/index.ts	Barrel exports establish public API for registry and result modules.
UI layout components with variants src/shared/ui/box.tsx, src/shared/ui/flex.tsx	Box and Flex components define cva variants for display and layout control. Both support asChild polymorphism and forward props.
UI form and interactive components src/shared/ui/button.tsx, src/shared/ui/checkbox.tsx, src/shared/ui/label.tsx, src/shared/ui/textarea.tsx	Form controls wrap Radix UI primitives or native elements, apply fixed and mergeable Tailwind styling, and include data attributes for hooks.
UI typography system with polymorphic variant support src/shared/ui/typography.tsx	Typography component supports variant-driven element selection (via VARIANT_TAGS), asChild composition, and optional tag override with as prop. Variants map to heading and text styles.
UI library public surface barrel export src/shared/ui/index.ts	Barrel re-exports all UI components and variant configurations to establish the shared UI module's public API.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Possibly related PRs

• rivodotlove/devbox#8: Introduces the registry and result modules whose public exports are now established via the kernel barrel in this PR.

Poem

🐰 Components in layers so neat,
Variants dance where style and logic meet,
Radix primitives wrapped with care and grace,
A UI library finds its place!

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title 'feat(shared): add UI primitives and kernel barrel' accurately describes the main changes—introduction of UI primitives and kernel barrel exports—and follows conventional commit conventions.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch feat/shared-ui-primitives

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Status	Name	Latest Commit	Preview URL	Updated (UTC)
✅ Deployment successful! View logs	devbox	d839a66	Commit Preview URL Branch Preview URL	Jun 02 2026, 02:41 PM