add .mandatory, update learn.sh and sync-skills.sh to use it

sync-skills.sh

@@ -1,19 +1,27 @@
 #!/bin/bash
-# Sync all skill folders from ClawSkills to ~/.openclaw/skills
+# Sync skills listed in .mandatory from ClawSkills to ~/.openclaw/skills
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 SKILLS_DIR="$HOME/.openclaw/skills"
+MANDATORY_FILE="${SCRIPT_DIR}/.mandatory"
 
 mkdir -p "$SKILLS_DIR"
 
-for folder in "$SCRIPT_DIR"/*/; do
-    folder_name=$(basename "$folder")
-    # Skip this script itself
-    if [[ "$folder_name" == "sync-skills.sh" ]]; then
-        continue
+if [[ ! -f "$MANDATORY_FILE" ]]; then
+    echo "Error: .mandatory not found at $MANDATORY_FILE"
+    exit 1
+fi
+
+while IFS= read -r skill_name || [[ -n "$skill_name" ]]; do
+    [[ -z "$skill_name" || "$skill_name" == \#* ]] && continue
+
+    skill_dir="${SCRIPT_DIR}/${skill_name}"
+    if [[ -d "$skill_dir" ]]; then
+        echo "Copying $skill_name to $SKILLS_DIR..."
+        cp -rf "$skill_dir" "$SKILLS_DIR/"
+    else
+        echo "Skipping (not found): $skill_name"
     fi
-    echo "Copying $folder_name to $SKILLS_DIR..."
-    cp -rf "$folder" "$SKILLS_DIR/"
-done
+done < "$MANDATORY_FILE"
 
 echo "Done!"