initial commit: docker test-build toolchain

Extracted from the .extras/ dir of the sbo-slackbuilds package repo, where it
grew from a throwaway helper into a standalone tool. Git history starts fresh;
the original 41-commit development log is preserved in HISTORY.md.

Contents: the test-build CLI (resolves a local SlackBuild's deps from a
configured SBo tree and builds it in a throwaway container, lints, caches deps),
the image-builder chain that produces the images it consumes, their pure-logic
self-checks, design specs/plans, an install.sh for ~/bin, and docs.

Licensed GPLv2-only.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/test-build-config.example b/test-build-config.example
new file mode 100644
index 0000000..a07b2c1
--- /dev/null
+++ b/test-build-config.example
@@ -0,0 +1,18 @@
+# test-build config. Copy to ~/.config/sbo-testbuild/config and edit.
+# Override the path with the TB_CONFIG environment variable.
+
+# Local SBo trees, one per target Slackware version.
+SBO_TREE_CURRENT="/home/danix/SBo/current"
+SBO_TREE_STABLE="/home/danix/SBo/15.0"
+
+# Ready image tags (built by a separate job, consumed here by tag).
+IMAGE_CURRENT="sbo-testbuild:current"
+IMAGE_STABLE="sbo-testbuild:15.0"
+
+# Where per-run logs land.
+LOG_ROOT="/home/danix/.cache/sbo-test-build"
+
+# Dependency package cache (host dir). Empty disables caching.
+# Namespaced internally by image digest, so it self-invalidates on image update
+# and keeps current vs 15.0 separate.
+PKG_CACHE="/home/danix/.cache/sbo-test-build/pkgcache"