a number of smaller fixes

• set version to 0.20.5
• test: remove froster command execution from test_data.sh
• test: add symlink creation to test data generation
• test: set symlink timestamps in test data generation
• fix: Use touch -h -m for symlinks in test_data.sh
• test: add integration test script
• refactor: Move test data generation to external script
• fix: rename conflicting script_dir variable in test script
• fix: add missing functions and call generate_test_data
• test: create test data dir in current working directory
• fix: exit archive command immediately after reset
• fix: set HOME environment variable for rclone execution
• fix: disable rclone AWS SSO check
• fix: run pipx install froster in foreground to prevent hang
• fix: use printf %s for spinner display
• style: Add ellipsis to installation message
• perf: add parallelism to rclone checksum
• fix: Add --s3-no-check-bucket flag for Ceph provider
• fix: Prevent archiving empty or metadata-only directories
• refactor: skip archiving dirs containing only subdirs/metadata