fix: pre-clean transient dirs + repeat cleanup before every mackup attempt

Root cause: Claude Code recreates ~/.claude/debug/latest (a dangling
symlink to the current debug session) almost immediately after it is
deleted. The old cleanup ran once before the retry loop, so any retry
after a 2s sleep would hit a freshly recreated symlink.

Fix: move _ssr_mackup_preclean() inside the retry loop so it runs
immediately before each mackup attempt, leaving no window for apps to
recreate problematic files.

Also remove known transient subdirectories by path before the generic
socket/dangling-link sweep:
  .claude/debug  .cursor/logs  .vscode/logs  .npm/_logs

Configurable via SSR_MACKUP_PRECLEAN_PATHS (space-separated, $HOME-relative).

Co-authored-by: Cursor <cursoragent@cursor.com>

lib/mackup.sh

@@ -262,28 +262,48 @@ ssr::mackup::backup() {
     fi
     [[ -n "$mackup_root" ]] && ssr::mackup::_materialize_icloud "$mackup_root"
 
-    # Pre-backup cleanup: remove file types that shutil.copy cannot handle.
-    #
-    # 1. Unix socket files (-type s) — runtime artefacts, recreated on app start.
-    #    Cause: shutil.Error [Errno 102] Operation not supported on socket
-    local socket_count
-    socket_count="$(find "$HOME" -type s 2>/dev/null | wc -l | tr -d ' ')"
-    if [[ "$socket_count" -gt 0 ]]; then
-        ssr::log "Removing $socket_count Unix socket file(s) before mackup backup (runtime artefacts)"
-        find "$HOME" -type s -delete 2>/dev/null || true
-    fi
+    # ---------------------------------------------------------------------------
+    # Pre-backup cleanup — remove artefacts that shutil.copytree cannot handle.
+    # Run this immediately before each mackup attempt so that apps (e.g. Claude
+    # Code) that recreate debug symlinks very quickly don't sneak back in.
+    # ---------------------------------------------------------------------------
+    _ssr_mackup_preclean() {
+        # Known transient subdirectories that apps recreate constantly.
+        # These contain debug logs / sockets, never real config.
+        # Extend via SSR_MACKUP_PRECLEAN_PATHS (space-separated $HOME-relative).
+        local -a transient_dirs=(
+            .claude/debug           # Claude Code debug session links
+            .cursor/logs            # Cursor IDE logs
+            .vscode/logs            # VS Code logs
+            .vscode-insiders/logs
+            .npm/_logs              # npm debug logs
+        )
+        local extra dir
+        for extra in ${SSR_MACKUP_PRECLEAN_PATHS:-}; do
+            transient_dirs+=("$extra")
+        done
+        for dir in "${transient_dirs[@]}"; do
+            [[ -e "$HOME/$dir" ]] && rm -rf "$HOME/$dir" 2>/dev/null || true
+        done
 
-    # 2. Dangling symlinks (-type l ! -e) — point to a non-existent target.
-    #    Cause: shutil.Error [Errno 2] No such file or directory: '<target>'
-    local dangling_count
-    dangling_count="$(find "$HOME" -type l ! -e 2>/dev/null | wc -l | tr -d ' ')"
-    if [[ "$dangling_count" -gt 0 ]]; then
-        ssr::log "Removing $dangling_count dangling symlink(s) before mackup backup"
-        find "$HOME" -type l ! -e -delete 2>/dev/null || true
-    fi
+        # 1. Unix socket files (-type s) — [Errno 102] Operation not supported.
+        local n; n="$(find "$HOME" -type s 2>/dev/null | wc -l | tr -d ' ')"
+        if [[ "$n" -gt 0 ]]; then
+            ssr::log "  pre-clean: removing $n socket file(s)"
+            find "$HOME" -type s -delete 2>/dev/null || true
+        fi
+
+        # 2. Dangling symlinks (-type l ! -e) — [Errno 2] No such file.
+        n="$(find "$HOME" -type l ! -e 2>/dev/null | wc -l | tr -d ' ')"
+        if [[ "$n" -gt 0 ]]; then
+            ssr::log "  pre-clean: removing $n dangling symlink(s)"
+            find "$HOME" -type l ! -e -delete 2>/dev/null || true
+        fi
+    }
 
     local attempt rc=0
     for attempt in 1 2 3; do
+        _ssr_mackup_preclean      # clean immediately before each attempt
         if mackup -f backup; then
             return 0
         fi