fix(core): remove debug code that runs in production builds

[yogeshwaran-c]

Description

Removes development-only debug code that was executing in production builds:

1. debug.jsx: window.props = this.props was exposing internal component props globally in all environments. Now wrapped in process.env.NODE_ENV === "development" check, which Webpack's DefinePlugin will dead-code eliminate in production builds.

2. examples-select.jsx: Default onSelect prop contained a console.log call with a FIXME comment ("remove before merging to master"). Replaced with a no-op function.

3. examples-select-value-retainer.jsx: Default onSelect and updateValue props contained console.log calls. Replaced with no-op functions.

Motivation and Context

Fixes #10521

• Security: window.props exposed internal application state to the browser console in production
• Console pollution: Debug log messages appeared in production builds
• Code quality: The FIXME comment in examples-select.jsx explicitly asked for the debug code to be removed

How Has This Been Tested?

• Verified the changes compile correctly
• The window.props assignment is now gated behind a development environment check
• The no-op functions maintain the same interface as before without side effects
• All existing tests should continue to pass since the debug code was not tested

Screenshots (if appropriate):

N/A

Checklist

My PR contains...

• No code changes (src/ is unmodified: changes to documentation, CI, metadata, etc.)
• Dependency changes (any modification to dependencies in package.json)
• Bug fixes (non-breaking change which fixes an issue)
• Improvements (misc. changes to existing features)
• Features (non-breaking change which adds functionality)

My changes...

• are breaking changes to a public API (config options, System API, major UI change, etc).
• are breaking changes to a private API (Redux, component props, utility functions, etc.).
• are breaking changes to a developer API (npm script behavior changes, new dev system dependencies, etc).
• are not breaking changes.

Documentation

• My changes do not require a change to the project documentation.
• My changes require a change to the project documentation.
• If yes to above: I have updated the documentation accordingly.

Automated tests

• My changes can not or do not need to be tested.
• My changes can and should be tested by unit and/or integration tests.
• If yes to above: I have added tests to cover my changes.
• If yes to above: I have taken care to cover edge cases in my tests.
• All new and existing tests passed.