sb-builder - Qt6 GUI to drive SlackBuild tooling on a build VM

Age	Commit message (Collapse)	Author	Files	Lines
30 hours	Add phase 1 implementation plan, refine spec	Danilo M.	1	-0/+2259
	The plan embeds code that was run in a scratch copy before writing it down (38 tests, helper stats against the real VM data). Drafting it settled a few details now reflected in the spec: version also returns the overlays, an upstream_branch helper key, a shared fmt module and a launcher, follow resuming on the next jobs poll instead of its own backoff, and sbpull returning sbshadow's exit status. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>