MLE-24763 Upgrading from jshint to eslint

[rjrudin]

No linting fixes yet. Changing from the older jshint to the modern eslint. The eslint config doesn't enforce whitespace yet, will do that in a later PR.

[Copilot]

Pull Request Overview

This PR migrates the project's linting infrastructure from jshint to eslint, introducing modern linting tooling while deferring whitespace/formatting enforcement to a future PR.

Key changes:

• Upgraded eslint from v8 to v9 with flat config format
• Replaced jshint with eslint in the gulp build pipeline
• Created comprehensive eslint configuration with many spacing rules temporarily disabled

Reviewed Changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated no comments.

File	Description
package.json	Updated eslint to v9.37.0, added gulp-eslint-new, removed jshint and gulp-jshint dependencies
gulpfile.js	Replaced jshint linting task with eslint, updated file glob pattern to explicitly match .js files
eslint.config.js	Added new flat config with rules matching previous jshint settings, spacing/formatting rules disabled for now
.jshintrc	Removed legacy jshint configuration file

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[github-actions]

Copyright Validation Results
Total: 4 | Passed: 2 | Failed: 0 | Skipped: 2 | at: 2025-10-16 16:51:29 UTC | commit: 14576cb

⏭️ Skipped (Excluded) Files

• package-lock.json
• package.json

✅ Valid Files

• eslint.config.js
• gulpfile.js

✅ All files have valid copyright headers!