Move devextreme-dist to packages and add documentation files

[alexslavr]

Cherry-pick of #33150 & #33232

[Copilot]

Pull request overview

This PR relocates the devextreme-dist workspace definition from a build-artifact folder into packages/ and ensures the published devextreme-dist output includes basic documentation files.

Changes:

• Removes packages/devextreme/artifacts/npm/devextreme-dist from pnpm workspaces and registers packages/devextreme-dist as the workspace package.
• Updates DevExtreme npm build pipeline to source devextreme-dist metadata from the new workspace package and to copy README.md/LICENSE.md into the publish output.
• Adds README.md and LICENSE.md for devextreme-dist and updates its package.json publish config.

Reviewed changes

Copilot reviewed 7 out of 8 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
pnpm-workspace.yaml	Stops treating the artifacts-based devextreme-dist folder as a workspace package.
pnpm-lock.yaml	Updates workspace importer entries to reflect packages/devextreme-dist and its publish directory.
packages/devextreme/gulpfile.js	Adjusts clean exclusions related to devextreme-dist artifacts.
packages/devextreme/build/gulp/npm.js	Builds devextreme-dist package metadata from the new workspace and copies README/LICENSE to the dist output.
packages/devextreme/.gitignore	Removes the exception for tracking an artifacts-based devextreme-dist/package.json.
packages/devextreme-dist/README.md	Adds package documentation for devextreme-dist.
packages/devextreme-dist/LICENSE.md	Adds licensing reference document for devextreme-dist.
packages/devextreme-dist/package.json	Adds publishConfig and minor formatting cleanup.

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

Comments suppressed due to low confidence (1)

packages/devextreme-dist/package.json:57

• packages/devextreme-dist/package.json is missing a license field. Other published packages in this repo set it (e.g., packages/devextreme/package.json uses "license": "SEE LICENSE IN README.md"). Since this package now ships its own LICENSE.md, consider adding an explicit license value (or SEE LICENSE IN LICENSE.md) to avoid npm metadata warnings and make licensing discoverable.