feat: harden user file handling and gate LaunchServices rebuild (#159)

- add ensure_user_dir/ensure_user_file helpers in lib/core/base.sh, including
  sudo-aware ownership correction under the invoking user’s home
- use the helpers across clean/optimize/purge/uninstall/whitelist to create
  cache and export files safely (no naked mkdir/touch), including log files and
  dry-run exports
- ensure purge stats/count files and update message caches are pre-created with
  safe permissions
- add Darwin version helpers and skip LaunchServices/dyld rebuild on macOS 15+,
  keeping the existing corruption protection for earlier versions
- guard brew cache timestamp writes and TCC permission flags with safe file
  creation to avoid root-owned artifacts

bin/clean.sh

@@ -159,6 +159,7 @@ start_section() {
 
     # Write section header to export list in dry-run mode
     if [[ "$DRY_RUN" == "true" ]]; then
+        ensure_user_file "$EXPORT_LIST_FILE"
         echo "" >> "$EXPORT_LIST_FILE"
         echo "=== $1 ===" >> "$EXPORT_LIST_FILE"
     fi
@@ -452,7 +453,7 @@ start_cleanup() {
         SYSTEM_CLEAN=false
 
         # Initialize export list file
-        mkdir -p "$(dirname "$EXPORT_LIST_FILE")"
+        ensure_user_file "$EXPORT_LIST_FILE"
         cat > "$EXPORT_LIST_FILE" << EOF
 # Mole Cleanup Preview - $(date '+%Y-%m-%d %H:%M:%S')
 #

bin/optimize.sh

@@ -200,7 +200,7 @@ cleanup_path() {
 ensure_directory() {
     local raw_path="$1"
     local expanded_path="${raw_path/#\~/$HOME}"
-    mkdir -p "$expanded_path" > /dev/null 2>&1 || true
+    ensure_user_dir "$expanded_path"
 }
 
 count_local_snapshots() {

bin/purge.sh

@@ -47,7 +47,9 @@ start_purge() {
 
     # Initialize stats file in user cache directory
     local stats_dir="${XDG_CACHE_HOME:-$HOME/.cache}/mole"
-    mkdir -p "$stats_dir"
+    ensure_user_dir "$stats_dir"
+    ensure_user_file "$stats_dir/purge_stats"
+    ensure_user_file "$stats_dir/purge_count"
     echo "0" > "$stats_dir/purge_stats"
     echo "0" > "$stats_dir/purge_count"
 }

bin/uninstall.sh

@@ -36,7 +36,7 @@ scan_applications() {
     local cache_ttl=86400 # 24 hours
     local force_rescan="${1:-false}"
 
-    mkdir -p "$cache_dir" 2> /dev/null
+    ensure_user_dir "$cache_dir"
 
     # Check if cache exists and is fresh
     if [[ $force_rescan == false && -f "$cache_file" ]]; then
@@ -310,6 +310,7 @@ scan_applications() {
         fi
     fi
 
+    ensure_user_file "$cache_file"
     cp "${temp_file}.sorted" "$cache_file" 2> /dev/null || true
 
     if [[ -f "${temp_file}.sorted" ]]; then

bin/uninstall_lib.sh

@@ -75,7 +75,7 @@ scan_applications() {
     local cache_ttl=86400 # 24 hours
     local force_rescan="${1:-false}"
 
-    mkdir -p "$cache_dir" 2> /dev/null
+    ensure_user_dir "$cache_dir"
 
     # Check if cache exists and is fresh
     if [[ $force_rescan == false && -f "$cache_file" ]]; then
@@ -344,6 +344,7 @@ scan_applications() {
     fi
 
     # Save to cache (simplified - no metadata)
+    ensure_user_file "$cache_file"
     cp "${temp_file}.sorted" "$cache_file" 2> /dev/null || true
 
     # Return sorted file