Feature/gulp to nx test env

[vorobey]

No description provided.

[Copilot]

Pull request overview

This PR continues the migration from Gulp tasks to Nx targets by introducing a test-env Nx target and moving the bundler-config watch workflow to Nx, supported by new capabilities in the concatenate-files executor (multi-pass concatenation and watch mode).

Changes:

• Enhanced devextreme-nx-infra-plugin:concatenate-files to support additionalPasses and watch/watchPaths, with E2E coverage for both.
• Added Nx targets in packages/devextreme/project.json for test-env and build:devextreme-bundler-config:watch, and updated Gulp tasks to delegate to Nx.
• Centralized chokidar as a root dev dependency (and removed it from devextreme-scss).

Reviewed changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
pnpm-lock.yaml	Moves chokidar lock entry from devextreme-scss to workspace root.
packages/nx-infra-plugin/src/executors/concatenate-files/schema.ts	Introduces ConcatenatePass and extends schema to support additional passes + watch options.
packages/nx-infra-plugin/src/executors/concatenate-files/schema.json	Adds JSON schema for additionalPasses, watch, and watchPaths.
packages/nx-infra-plugin/src/executors/concatenate-files/executor.e2e.spec.ts	Adds E2E coverage for additionalPasses and watch rebuild behavior.
packages/nx-infra-plugin/src/executors/concatenate-files/concatenate-files.impl.ts	Implements multi-pass execution and watch mode (via chokidar).
packages/nx-infra-plugin/AGENTS.md	Documents newly migrated gulp tasks and their Nx equivalents.
packages/devextreme/project.json	Adds build:devextreme-bundler-config:watch and test-env Nx targets.
packages/devextreme/gulpfile.js	Delegates gulp test-env to pnpm nx test-env devextreme.
packages/devextreme/build/gulp/bundler-config.js	Replaces Gulp pipeline with Nx delegation for bundler-config + watch.
packages/devextreme-scss/package.json	Removes chokidar from package-local devDependencies.
package.json	Adds chokidar to workspace root devDependencies.

Files not reviewed (1)

• pnpm-lock.yaml: Generated file