chore: add feature flag report to package

[rix0rrr]

Include a file recommended-feature-flags.json into the aws-cdk-lib package.

At build time, the CLI will copy the current aws-cdk-lib and constructs version, as well as the feature flag report, into its own package directory, and it will use those to initialize a new project.

This decouples the init version number from the CLI version number, and it removes the need for the CLI to read cx-api at init time.

Closes https://github.com/aws/aws-cdk-cli/issues/7

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[aws-cdk-automation]

The pull request linter has failed. See the aws-cdk-automation comment below for failure reasons. If you believe this pull request should receive an exemption, please comment and provide a justification.

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[codecov]

Codecov Report

Attention: Patch coverage is 84.61538% with 2 lines in your changes missing coverage. Please review.

Project coverage is 79.21%. Comparing base (cbacf4d) to head (1e2902d).
Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #32607      +/-   ##
==========================================
+ Coverage   79.13%   79.21%   +0.08%     
==========================================
  Files         107      107              
  Lines        7131     7154      +23     
  Branches     1319     1326       +7     
==========================================
+ Hits         5643     5667      +24     
  Misses       1304     1304              
+ Partials      184      183       -1     

Flag	Coverage Δ
suite.unit	79.21% <84.61%> (+0.08%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
packages/aws-cdk	79.21% <84.61%> (+0.08%)	⬆️

[aws-cdk-automation]

AWS CodeBuild CI Report

• CodeBuild project: AutoBuildv2Project1C6BFA3F-wQm2hXv2jqQv
• Commit ID: 1e2902d
• Result: SUCCEEDED
• Build Logs (available for 30 days)

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[aws-cdk-automation]

➡️ PR build request submitted to test-main-pipeline ⬅️

A maintainer must now check the pipeline and add the pr-linter/cli-integ-tested label once the pipeline succeeds.

[aws-cdk-automation]

The pull request linter fails with the following errors:

❌ CLI code has changed. A maintainer must run the code through the testing pipeline (git fetch origin pull/32607/head && git push -f origin FETCH_HEAD:test-main-pipeline), then add the 'pr-linter/cli-integ-tested' label when the pipeline succeeds.

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