Externalize config; mirror mountpoint+auto-mount, MIRROR_TREE, --terse

Config now lives outside the script in $SBO_BATCH_CONFIG (default
~/.config/sbo-batch-tester/config), sourced at load. Script ships empty
defaults plus config.example as the template; require_config (in validate_env
and init_base) hard-fails a real run when the config is missing or has not set
SLACKWARE_BASE / LOCAL_MIRROR_15 / SBO_TREE_ROOTS.

LOCAL_MIRROR_15 is now the NFS mountpoint, not the tree root. The Slackware
tree is derived as MIRROR_TREE=$LOCAL_MIRROR_15/slackware64-$VERSION (holds
ChangeLog.txt, slackware64/, patches/); all mirror content reads use it. The
mountpoint is checked with mountpoint -q and auto-mounted (mount
$LOCAL_MIRROR_15) when the noauto fstab entry is not mounted, left mounted
after the run.

installpkg/upgradepkg run with --terse for cleaner output. Docs updated.

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

1 files changed, 13 insertions, 6 deletions

diff --git a/README.md b/README.md
index b29542c..6a15ff0 100644
--- a/README.md
+++ b/README.md
@@ -26,15 +26,22 @@ current-vs-15.0 drift bites.
 
 ## Prerequisites
 
-You need three things in place, all configured in the CONFIG block at the top
-of `sbo-batch-test`:
+Configuration lives in an external file, not in the script. Copy `config.example`
+to `~/.config/sbo-batch-tester/config` and edit it (the tool runs as root, so
+that is `/root/.config/sbo-batch-tester/config`). Override the path with the
+`SBO_BATCH_CONFIG` environment variable. You need three things set in it:
 
 1. **`SLACKWARE_BASE`** - a LOCAL (non-NFS) full Slackware 15.0 install tree.
    This is the overlay lowerdir. It MUST be local (ext4/xfs). overlayfs over an
    NFS lowerdir is fragile and a known source of intermittent failures.
 
-2. **`LOCAL_MIRROR_15`** - the NFS-mounted Slackware 15.0 mirror. Used only as a
-   package SOURCE to populate and patch `SLACKWARE_BASE`. Read-only is fine.
+2. **`LOCAL_MIRROR_15`** - the NFS mountpoint for the Slackware 15.0 mirror.
+   Point it at the mount root itself; the actual tree (ChangeLog.txt,
+   slackware64/, patches/) is found one level down at
+   `$LOCAL_MIRROR_15/slackware64-$VERSION`. Used only as a package SOURCE to
+   populate and patch `SLACKWARE_BASE`. Read-only is fine. If the fstab entry is
+   `noauto`, the script auto-mounts it (`mount $LOCAL_MIRROR_15`) when absent and
+   leaves it mounted after the run.
 
 3. **`SBO_TREE_ROOTS`** - one or more LOCAL SBo tree roots, resolved in order
    (first match wins). Standard SBo layout
@@ -49,8 +56,8 @@ Populate from the NFS mirror with the FULL package set, not a minimal install.
 A minimal base causes false "missing dependency" results that would not happen
 on a normal user's full Slackware install.
 
-Set `SLACKWARE_BASE` and `LOCAL_MIRROR_15` in the script's CONFIG block, then
-run once as root:
+Set `SLACKWARE_BASE` and `LOCAL_MIRROR_15` in your config file, then run once
+as root:
 
 ```sh
 sbo-batch-test --init-base