Clean Up Tracked Build Artefacts for the SIST 1.0.0 Release

[harryswift01]

Summary

This PR cleans up the SIST repository ahead of the 1.0.0 release by removing tracked build artefacts and ensuring generated files are ignored correctly.

The repository has also been rebuilt and tested after the cleanup to confirm that SIST can still be built from source without changing the established scientific results.

Changes

Repository cleanup:

• Removed the tracked cmake-build-debug/ directory.
• Removed tracked C++ object files from trans_three/ and trans_compete/.
• Removed the tracked qsidd executables.
• Removed generated depend files from version control.
• Reviewed the existing files under example/ and retained them as intentional worked-example inputs and outputs.

Git ignore rules:

• Added ignore rules for generated SIST qsidd executables.
• Added ignore rules for generated dependency files.
• Retained the existing rules for object files, build directories, documentation output, Python artefacts, and regression test output.
• Left irf308.linux.exe unchanged pending the separate platform and dependency investigation.

Build and regression verification:

• Rebuilt both trans_three and trans_compete successfully from source.
• Confirmed regenerated build artefacts do not appear as untracked files.
• Ran the full regression suite successfully after cleanup.
• Confirmed the maintained scientific baseline remains unchanged.

Impact

• Provides a cleaner and more maintainable source repository.
• Prevents stale compiled artefacts from being accidentally used.
• Ensures SIST executables are built from the maintained source rather than inherited binaries.
• Improves reproducibility ahead of packaging and the SIST 1.0.0 release.
• Does not intentionally change scientific calculations or command-line behaviour.

[jimboid]

Looks like sensible changes taking account for removing previously and erroneously committed artifacts to history.