feat: auto stable selectors.

[knightedcodemonkey]

• fixes Auto-generate stable class variants from source styles #24

[codecov]

Codecov Report

❌ Patch coverage is 89.85507% with 42 lines in your changes missing coverage. Please review.
✅ Project coverage is 91.57%. Comparing base (f8cf325) to head (3063479).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
packages/css/src/loader.ts	85.71%	16 Missing and 2 partials ⚠️
packages/css/src/autoStableSelectors.ts	90.11%	14 Missing and 3 partials ⚠️
packages/css/src/css.ts	92.78%	7 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #54      +/-   ##
==========================================
- Coverage   91.86%   91.57%   -0.29%     
==========================================
  Files          12       13       +1     
  Lines        3281     3668     +387     
  Branches      572      644      +72     
==========================================
+ Hits         3014     3359     +345     
- Misses        244      281      +37     
- Partials       23       28       +5     

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[Copilot]

Pull request overview

This PR adds an autoStable feature that automatically duplicates CSS class selectors with deterministic, stable namespaced class names (e.g., .foo becomes .foo, .knighted-foo). This functionality works for both plain CSS and CSS Modules, allowing for stable test selectors while maintaining CSS Modules' hashing benefits.

Changes:

• Implements autoStable option in the CSS loader with configurable namespace, include/exclude filters
• Integrates with LightningCSS visitor API for plain CSS transformation and post-processes CSS Modules exports
• Adds comprehensive test coverage across unit, integration, and e2e tests with new demo application

Reviewed changes

Copilot reviewed 29 out of 31 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
packages/css/src/autoStableSelectors.ts	Core implementation of autoStable visitor for LightningCSS transformation
packages/css/src/css.ts	Integration of autoStable into cssWithMeta with visitor composition
packages/css/src/loader.ts	Webpack loader integration with CSS Modules export merging
packages/css/src/generateTypes.ts	CLI support for autoStable type generation
packages/css/test/*.test.ts	Comprehensive test coverage for autoStable functionality
packages/playwright/src/auto-stable/*	Demo implementation with React/Lit integration
packages/playwright/test/auto-stable.spec.ts	E2E tests for autoStable demo
packages/playwright/*.config.js	Build configuration updates for webpack/rspack
docs/loader.md	Documentation for autoStable feature
package.json	Version bump to 1.1.0-rc.0 and dependency updates

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