fix: Fix SDK version metadata in UserAgent header

[sichanyoo]

Issue #

1729

Description of changes

• During prepare release, write the new current version to AWSClientRuntime/Resources/sdk-version.txt as well, and use that to initialize user agent middleware during runtime similar to how partitions data is loaded.

New/existing dependencies impact assessment, if applicable

Conventional Commits

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[dayaffe]

Non-Blocking: This may be the best solution but it gives me pause that we will be storing a duplicate of package.version in a sdk-version.txt. I understand the reasons for doing so but I wonder if there is either a better way or an opportunity for refactoring so that we only have a single file with the version.

[jbelkins]

I don't want to mix auto-generated files into AWSClientRuntime. That complicates our build/release pipeline.

I thought we had discussed using the contents of Package.version.next to write the version string into the client during codegen. Did that approach not work?

[sichanyoo]

@jbelkins
I decided to take this route instead of using Package.version.next during codegen, after finding out that reading a file in Kotlin that's not placed under resources/ is tricky / dangerous. You can give it relative path or an absolute path of the file to read. Relative path gets resolved against where-ever the program was initiated from (e.g., from ~ if it was initiated from there, instead of project root). And as for absolute path, we don't have that available during codegen.