feat: Create CfnFlexCluster

[lantoli]

Proposed changes

Create CfnFlexCluster. Generate index.ts file from the corresponding CloudFormation resource. Add the other supporting files.

Jira ticket: CLOUDP-342590

Link to any related issue(s):

Type of change:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as
  expected)
• This change requires a documentation update

Required Checklist:

• I have signed the MongoDB CLA
• I have added tests that prove my fix is effective or that my feature works
• I have added any necessary documentation (if appropriate)
• I have run make fmt and formatted my code
• I have tested the CDK constructor in a CFN stack. See TESTING.md
• If changes include removal or addition of 3rd party GitHub actions, I updated our internal document. Reach out to the APIx Integration slack channel to get access to the internal document.

Further comments

[Copilot]

Pull Request Overview

This PR creates a new CfnFlexCluster resource for MongoDB Atlas Flex clusters, which are flexible, scalable, and cost-optimized clusters for low-traffic applications with variable workloads.

Key changes:

• Generates CloudFormation resource bindings for MongoDB::Atlas::FlexCluster
• Adds comprehensive type definitions for flex cluster configuration
• Provides example implementation and integration test

Reviewed Changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/l1-resources/flex-cluster/index.ts	Core flex cluster resource with TypeScript interfaces and CloudFormation bindings
src/l1-resources/flex-cluster/integ.default.ts	Integration test demonstrating basic flex cluster creation
src/l1-resources/flex-cluster/README.md	Documentation with usage examples and API references
src/index.ts	Main export file updated to include flex cluster types with conflict resolution
examples/l1-resources/flex-cluster.ts	Complete example showing project and flex cluster creation
API.md	Auto-generated API documentation for the new flex cluster resource
.projenrc.js	Build configuration updated with additional ignore patterns
.npmignore	Package ignore list updated to exclude development files

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[marcosuma]

n00b question, why do we mention Node.js here

[lantoli]

similarly to doc in the other resources, they can also be used in Java, C#, Go, Python, this directoy has the Node resource definition

[marcosuma]

is this copy / pasted from somewhere? Can you add a link to the official MongoDB ATlas docs? https://www.mongodb.com/docs/atlas/create-database-deployment/#flex-clusters

[lantoli]

changed to use the link instead: 197861a

[lantoli]

BTW, this is one of the files that the docs team will update