[release/9.0] [Static Assets] Improve development experience

[github-actions]

Backport of #57671 to release/9.0

/cc @javiercn

[Static Assets] Improve development experience

Fixes an issue when running a published app on Development and provides a better error when static web assets are not enabled during development

Description

• Addresses two issues that we found during development:
  • When the user publishes the app and runs against the Development environment:
    • Some logic that is pivoted on based on the Environment and is only used during development (Build as opposed to Publish) interferes with the output and causes issues on the running app.
  • When the app runs during development, but Static Web Assets are not enabled for some reason:
    • The app isn't able to find some static files and errors out.
    • The fix improves the experience by detecting this situation and logging a warning on the console with instructions on how to enable static web assets explicitly.

Customer Impact

• Running in Docker 'Regular Mode' in Visual Studio breaks as the app runs the published output with Development environment.
• Running the app during development with a custom environment or without a launch profile will cause some static files to not be found.

Regression?

• Yes
• No

8.0 and earlier, the published output was runnable in Development environment. For example in Docker containers regular mode (how the issue was found).

Risk

• High
• Medium
• Low

The changes uses information that we produce during the build (Build and Publish) to differentiate between the two scenarios and disable the development functionality for the published output and provide a better error message when static web assets are not enabled during development.

Verification

• Manual (required)
• Automated

Packaging changes reviewed?

• Yes
• No
• N/A

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When servicing release/2.1

• Make necessary changes in eng/PatchConfig.props