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, 69 insertions, 0 deletions

diff --git a/image-builder/README b/image-builder/README
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+sbo-testbuild image builder
+===========================
+
+Builds the docker images that test-build consumes:
+  docker.noland.dnx:5000/sbo-testbuild:current
+  docker.noland.dnx:5000/sbo-testbuild:15.0
+
+Three scripts, chained (see docs/specs/2026-07-13-image-builder-design.md):
+  bootstrap.sh           sbo-base:{ver}       FROM scratch, base pkgs from NAS
+  build-full-image.sh    sbo-full:{ver}       FROM base, all series
+  build-sbo-testbuild.sh sbo-testbuild:{ver}  FROM full, + sbopkg + tools
+
+All settings live in ./config.
+
+VM setup (docker.noland.dnx, Slackware x86_64, 4 vCPU / 4 GB / 80 GB)
+--------------------------------------------------------------------
+1. Install docker; enable the daemon.
+
+2. NFS-mount the two NAS trees read-only, named to match:
+     /mnt/nas/slackware64-current   -> -current mirror tree
+     /mnt/nas/slackware64-15.0      -> 15.0 mirror tree
+   Each is a full mirror (PACKAGES.TXT, ChangeLog.txt, slackware64/, patches/,
+   extra/). Root must be able to read them (bootstrap runs installpkg as root).
+
+3. Run a LAN registry:
+     docker run -d --restart=always -p 5000:5000 \
+       -v /opt/registry/data:/var/lib/registry --name registry registry:2
+
+4. Mark the registry insecure (plain HTTP) on the VM AND every pulling client
+   (this dev box, the buildsystem VM). In /etc/docker/daemon.json:
+     { "insecure-registries": ["docker.noland.dnx:5000"] }
+   then restart docker.
+
+5. Drop the two prebuilt packages (built once, re-drop on upstream bumps):
+     /opt/sbo-testbuild/pkgs/sbopkg-*.txz
+     /opt/sbo-testbuild/pkgs/sbo-maintainer-tools-*.txz
+
+6. Install the nightly cron (root). The NAS repos sync at 01:00 and 02:00, so
+   the chain runs after and both variants are ready well before the ~09:00 work
+   start. No --force: each script self-gates (bootstrap on the ChangeLog hash,
+   full-image on the base-image digest, build-sbo-testbuild on the full-image
+   digest + tools .txz hash), so an unchanged night is a cheap no-op. -current
+   moves daily and rebuilds most nights; 15.0 is frozen stable and rebuilds only
+   on a real repo update. Deployed schedule on docker.noland.dnx:
+      # -current (ready ~04:35)
+      0  3 * * *  /path/to/sbo-dockerbuild/image-builder/bootstrap.sh           --version current >> /var/log/sbo-testbuild.log 2>&1
+     20  3 * * *  /path/to/sbo-dockerbuild/image-builder/build-full-image.sh    --version current >> /var/log/sbo-testbuild.log 2>&1
+     30  4 * * *  /path/to/sbo-dockerbuild/image-builder/build-sbo-testbuild.sh --version current >> /var/log/sbo-testbuild.log 2>&1
+      # 15.0 (ready ~06:35)
+      0  5 * * *  /path/to/sbo-dockerbuild/image-builder/bootstrap.sh           --version 15.0 >> /var/log/sbo-testbuild.log 2>&1
+     20  5 * * *  /path/to/sbo-dockerbuild/image-builder/build-full-image.sh    --version 15.0 >> /var/log/sbo-testbuild.log 2>&1
+     30  6 * * *  /path/to/sbo-dockerbuild/image-builder/build-sbo-testbuild.sh --version 15.0 >> /var/log/sbo-testbuild.log 2>&1
+
+7. Ensure docker.noland.dnx resolves on the LAN (static IP or DNS).
+
+Manual first run
+----------------
+   ./bootstrap.sh --version current --force
+   ./build-full-image.sh --version current --force
+   ./build-sbo-testbuild.sh --version current --force
+Then confirm:
+   docker pull docker.noland.dnx:5000/sbo-testbuild:current
+   docker run --rm docker.noland.dnx:5000/sbo-testbuild:current sbopkg -V
+
+Flags: --force (rebuild unconditionally), --version <current|15.0> (one variant).
+
+Tests
+-----
+   bash test-image-builder.sh     # pure-logic self-check, no docker