fix(sync): skip OpenClaw variant branch when variants/open is absent (#222)

Makes the `variants/open/` sync steps in `scripts/sync.sh` conditional on
the directory actually existing in the source tree. The script is shared
between the public and private repos of last30days-skill, but the OpenClaw
variant only lives in the private repo (it's sanitized via
`strip_for_openclaw.py` and published separately to ClawhHub). When the
script runs from a checkout of the public repo, the variants/open paths
don't exist and the unconditional `rsync` and `sync_target` calls error
out immediately.

Changes:

- `sync_target()` now only creates `variants/open/references` and rsyncs
  `variants/open/` when `$SRC/variants/open` exists.
- The trailing `sync_target "$OPENCLAW_TARGET" ...` call is now gated by
  the same check, with an explanatory skip message when the directory is
  absent.

No behavior change when running from the private repo (which has
`variants/open/`). When running from the public repo, the script now
completes its COMMON_TARGETS loop without erroring.

This also closes out the confusion from PR #211, where a contributor saw
the broken `variants/open/` reference and tried to add the variant back
to the public repo. The real fix was making the script tolerate the
absence, not recreating the directory.

Co-authored-by: Matt Van Horn <455140+mvanhorn@users.noreply.github.com>

scripts/sync.sh

@@ -24,7 +24,7 @@ sync_target() {
 
   echo ""
   echo "--- Syncing to $target ---"
-  mkdir -p "$target/scripts/lib" "$target/variants/open/references"
+  mkdir -p "$target/scripts/lib"
 
   cp "$skill_md" "$target/SKILL.md"
 
@@ -35,7 +35,13 @@ sync_target() {
     "$SRC/scripts/store.py" \
     "$target/scripts/"
   rsync -a "$SRC/scripts/lib/"*.py "$target/scripts/lib/"
+
+  # The OpenClaw variant lives in the private repo only. Skip cleanly when
+  # running this script from the public repo where variants/open does not exist.
+  if [ -d "$SRC/variants/open" ]; then
+    mkdir -p "$target/variants/open/references"
     rsync -a "$SRC/variants/open/" "$target/variants/open/"
+  fi
 
   if [ -d "$SRC/scripts/lib/vendor" ]; then
     rsync -a "$SRC/scripts/lib/vendor" "$target/scripts/lib/"
@@ -63,7 +69,16 @@ for t in "${COMMON_TARGETS[@]}"; do
   sync_target "$t" "$SRC/SKILL.md"
 done
 
-sync_target "$OPENCLAW_TARGET" "$SRC/variants/open/SKILL.md"
+# OpenClaw sync only runs when the private-repo OpenClaw variant is present
+# in the source tree. The public repo does not ship variants/open (the variant
+# is sanitized via strip_for_openclaw.py and published separately from
+# last30days-skill-private).
+if [ -d "$SRC/variants/open" ]; then
+  sync_target "$OPENCLAW_TARGET" "$SRC/variants/open/SKILL.md"
+else
+  echo ""
+  echo "Skipping OpenClaw target (no variants/open in this repo)"
+fi
 
 echo ""
 echo "Sync complete."