Cleanup lambda image stuff

[dwhswenson]

Two main changes here:

1. Removed build_args from the lambda-image-build module (no longer passing additional Docker args; at least, not until/unless needed)
2. Renamed lambda-container -> lambda-image-republish, which I think is both a more clear name, and also aligns better with the lambda-image-build module name.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.36%. Comparing base (345e24d) to head (e71cc7e).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #10   +/-   ##
=======================================
  Coverage   98.36%   98.36%           
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  Files           8        8           
  Lines         306      306           
=======================================
  Hits          301      301           
  Misses          5        5           

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[Copilot]

Pull request overview

This PR performs a cleanup of the Lambda container image management modules by removing unused build arguments and renaming a module for better clarity.

Changes:

• Removed build_args parameter from the lambda-image-build module as it's not currently needed
• Renamed lambda-container module to lambda-image-republish for improved naming consistency
• Updated all references in examples and documentation to reflect the module rename

Reviewed changes

Copilot reviewed 6 out of 10 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
modules/lambda-image-republish/versions.tf	New file defining Terraform and AWS provider version constraints for the renamed module
modules/lambda-image-republish/variables.tf	New file defining input variables for image republishing functionality
modules/lambda-image-republish/outputs.tf	New file defining outputs including image URIs and repository details
modules/lambda-image-republish/main.tf	New file implementing ECR repository creation and Docker image republishing logic
modules/lambda-image-build/variables.tf	Removed unused build_args variable definition
modules/lambda-image-build/main.tf	Removed build_args logic and simplified the docker build command
examples/basic/variables.tf	Removed build_args variable from example
examples/basic/main.tf	Updated module source reference from lambda-container to lambda-image-republish and removed build_args parameter
PLAN.md	Updated module name references from lambda-container to lambda-image-republish in project plan
IDEA.md	Updated module name reference in usage example

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