feat: ElasticLoadBalancingV2 TargetGroups, provisioned concurrency support

[khvn26]

Proposed changes

• Added ElasticLoadBalancingV2 TargetGroups support.
• Added support for functions with provisioned concurrency/SnapStart configured via Serverless.
• Added package @flagsmith scope, an NPM publish job triggered by GitHub releases, and bumped the package version.

Types of changes

What types of changes does your code introduce to the plugin?

• 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)

Checklist

• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

Further comments

The logic to determine whether a given function has provisioned concurrency/SnapStart configured is simplifed greatly on behalf of the framework's internal code that sets a targetAlias property to the function configuration in any of those cases. This is not documented anywhere, but that code has been stable across both the major versions. For greater compatibility with other plugins that may rely on this, we set and/or update the functions' targetAliases with proper names and logical IDs.