Summary

synthorg update pulls new container images but never removes old ones. Over multiple updates, stale images accumulate and waste disk space -- especially since images are digest-pinned (each version is a distinct layer set). Additionally, on Windows the old CLI binary is renamed to .old.*.tmp before replacement but cleanup relies on os.Remove in the same process; if the re-exec happens before that remove, or if the remove fails silently, stale .old.*.tmp files may persist.

Scope

1. Container image cleanup (uninstall)

PR #590 adds image cleanup to synthorg uninstall:

• Lists ghcr.io/aureliolo/synthorg-* images with sizes
• Prompts user for confirmation
• Removes via docker rmi --force by image ID

2. Windows binary auto-deletion (uninstall)

PR #590 replaces the manual PowerShell instruction with automatic cleanup:

• Writes a temp .bat file that polls tasklist until the CLI PID exits
• Deletes the binary, empty parent dirs, and the .bat itself
• Falls back to manual PowerShell instruction if spawn fails

3. Container image cleanup (update) -- REMAINING

After pullAndPersist succeeds and before restartIfRunning, offer to prune the previous version's images:

• Track the previous image tag/digests (from state.ImageTag / state.VerifiedDigests before update)
• After successful pull + persist, remove the old images (docker rmi the previous digest-pinned refs)
• Prompt user for confirmation in interactive mode; auto-accept in non-interactive
• Optionally run docker image prune --filter dangling=true to clean up any orphaned layers
• Report disk space reclaimed

4. Windows stale .old.*.tmp cleanup on next invocation -- REMAINING

The selfupdate.ReplaceAt function on Windows:

1. Creates a .old.*.tmp temp file
2. Renames the current binary to that temp path
3. Renames the new binary into place
4. Calls os.Remove(oldPath) -- best-effort

Remaining work:

• On next synthorg invocation, scan the binary's directory for *.old.*.tmp files and remove them
• Add a test that verifies no stale .old.*.tmp files remain after a simulated update cycle

Acceptance Criteria

• Old container images are removed during uninstall (with user confirmation) -- PR fix(cli): auto-delete binary on Windows, prune images, fix GoReleaser #590
• Old container images are removed after successful update (with user confirmation)
• Disk space savings reported to user
• On Windows, binary auto-deleted after uninstall via temp .bat -- PR fix(cli): auto-delete binary on Windows, prune images, fix GoReleaser #590
• On Windows, stale .old.*.tmp binary files are cleaned up on next invocation
• Tests cover both cleanup paths
• Non-interactive mode auto-accepts cleanup (no leftover images in CI)

Context

Discovered during PR #576 (CLI update compose refresh). The update flow was audited and this gap identified.