Clean up old test-env directory and finalize test-tmp implementation

test-env/extracted-with-manifest/test/testfile.txt

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test-env/extracted/test/testfile.txt

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test/README.md

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+# Testing the Tarballer Utility
+
+This directory contains test scripts for validating the functionality of the Tarballer utility.
+
+## Test Environment
+
+All tests run in a Docker container with temporary files stored in the `/test-tmp` directory. This directory is:
+
+1. Git-ignored to prevent cluttering the repository
+2. Automatically created by the Docker container
+3. Cleaned up after tests complete (unless you specify otherwise)
+
+## Running Tests
+
+To run the tests, use Docker Compose from the project root:
+
+```bash
+# Build and run all tests
+docker compose up --build
+
+# Run only the basic test
+docker compose run tarballer /bin/test.sh basic
+
+# Run only the tar comparison test
+docker compose run tarballer /bin/test.sh tar
+
+# Keep temporary files after tests (for debugging)
+docker compose run tarballer /bin/test.sh all 1
+```
+
+## Test Types
+
+The test script (`test.sh`) supports several test types:
+
+1. `basic` - Tests basic tarball creation and extraction with various file types and symlinks
+2. `tar` - Compares our utility against standard tar functionality
+3. `all` - Runs all tests (default)
+4. `clean` - Just cleans up temporary files
+
+## Test Directory Structure
+
+The tests create the following structure in the `/test-tmp` directory:
+
+- `/test-tmp/complex/` - Directory with complex nested structure for basic test
+- `/test-tmp/complex-extracted/` - Where the complex test tarball is extracted
+- `/test-tmp/standard-test/` - Directory with sample app structure for tar comparison
+- `/test-tmp/standard-extracted/` - Where our utility's tarball is extracted
+- `/test-tmp/reference-extracted/` - Where standard tar's tarball is extracted
+
+## Manual Testing
+
+If you need to manually test the tarballer utility, you can:
+
+1. Build the binaries: `docker compose up --build`
+2. Use the binaries in `./bin/` directory:
+   ```bash
+   # Create a tarball
+   ./bin/tarballer-darwin -source /path/to/source -output output.tar.gz -prefix myapp
+   
+   # Extract and verify a tarball
+   ./bin/tarballer-darwin -extract -output output.tar.gz -extractdir /path/to/extract
+   ```
+
+## Modifying Tests
+
+When modifying tests, ensure any temporary files are created within the `/test-tmp` directory structure to keep the repository clean.