feat: Add web-core-wasm package

[PupilTong]

pick rust files

This is a part of #1937

Summary by CodeRabbit

• New Features

  • Introduces a WebAssembly "web-core" package: CSS tokenization & transformation, inline-style rules, template decoding/materialization, DOM element APIs (dataset/config/style), runtime event dispatch, JS bindings, and a compact operation/bytecode layer for client runtime.

• Tests

  • CI, linting and test steps now run with all feature flags enabled to improve coverage.

• Chores

  • Workspace updated with the new package and a workspace dependency; editor settings adjusted to analyze all features.

• Documentation

  • Developer-facing docs added for the new WASM web-core package.

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Checklist

• Tests updated (or not required).
• Documentation updated (or not required).
• Changeset added, and when a BREAKING CHANGE occurs, it needs to be clearly marked (or not required).