refactor: one ~/.mackup/ssr-<name>.cfg per dot-dir instead of combined file

Each discovered dot-dir now gets its own Mackup app definition:
  .claude  → ~/.mackup/ssr-claude.cfg
  .cursor  → ~/.mackup/ssr-cursor.cfg
  .config/gh → ~/.mackup/ssr-config-gh.cfg
  …

This matches Mackup's own convention, keeps definitions independent,
and makes it easy to add/remove individual apps. The old combined
ssr-custom.cfg is removed automatically on the next sync run.

Files are written idempotently (skipped when content is unchanged).

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

lib/mackup.sh

@@ -41,29 +41,57 @@ _SSR_MACKUP_SKIP=(
     .ssh .gnupg .aws .azure .gcloud .config/gcloud
 )
 
-# Generate (or refresh) ~/.mackup/ssr-custom.cfg with:
-#   1. Curated entries that exist in $HOME and are not yet in the Mackup backup.
-#   2. Any dot-dir discovered in $HOME that is not in the skip list and not
-#      already materialised in the Mackup backup directory.
-#
-# The file is picked up automatically by `mackup backup/restore`.
-# Idempotent: re-running overwrites the previous version.
-ssr::mackup::generate_custom_cfg() {
-    local mackup_dir="$1"   # the cloud Mackup backup directory
-    local cfg_dir="$HOME/.mackup"
-    local cfg_file="$cfg_dir/ssr-custom.cfg"
+# Derive a safe Mackup app-name and filename from a dot-path.
+# Examples:  .claude → ssr-claude      .config/gh → ssr-config-gh
+_ssr_mackup_cfg_name() {
+    local path="$1"
+    local name="${path#.}"          # strip leading dot
+    name="${name//\//-}"            # slashes → dashes
+    name="${name//_/-}"             # underscores → dashes
+    name="$(printf '%s' "$name" | tr '[:upper:]' '[:lower:]')"
+    printf 'ssr-%s' "$name"
+}
 
+# Write a single ~/.mackup/<name>.cfg for one dot-path.
+# Skips writing if the file already exists and its content matches
+# (idempotent on repeated syncs).
+_ssr_mackup_write_cfg() {
+    local cfg_dir="$1" item="$2"
+    local app_name; app_name="$(_ssr_mackup_cfg_name "$item")"
+    local cfg_file="$cfg_dir/${app_name}.cfg"
+
+    local desired
+    desired="$(printf '[application]\nname = %s\n\n[configuration_files]\n%s\n' \
+        "$app_name" "$item")"
+
+    if [[ -f "$cfg_file" ]] && [[ "$(cat "$cfg_file")" == "$desired" ]]; then
+        return 0   # already up-to-date
+    fi
+
+    printf '%s\n' "$desired" > "$cfg_file"
+}
+
+# Generate one ~/.mackup/ssr-<name>.cfg per uncovered dot-dir/file.
+#   1. Curated entries that exist in $HOME and are not yet in the Mackup backup.
+#   2. Auto-discovered dot-dirs in $HOME not in the skip list and not in backup.
+#
+# Removes the old combined ssr-custom.cfg if found (migration from old format).
+# Each file is picked up automatically by `mackup backup/restore`.
+ssr::mackup::generate_custom_cfg() {
+    local mackup_dir="$1"
+    local cfg_dir="$HOME/.mackup"
     mkdir -p "$cfg_dir"
 
-    # Build a fast lookup set from the skip list.
+    # Remove legacy combined file if present.
+    [[ -f "$cfg_dir/ssr-custom.cfg" ]] && rm -f "$cfg_dir/ssr-custom.cfg"
+
     local skip_set=" ${_SSR_MACKUP_SKIP[*]} "
 
-    # Helper: is <item> already in the Mackup backup?
     _in_backup() { [[ -e "$mackup_dir/$1" ]]; }
 
     local -a items=()
 
-    # 1. Curated entries (exist on disk, not yet backed up).
+    # 1. Curated + user-defined extras.
     local item
     for item in "${_SSR_MACKUP_CURATED[@]}" ${SSR_MACKUP_EXTRA_PATHS:-}; do
         [[ -e "$HOME/$item" ]] || continue
@@ -71,15 +99,12 @@ ssr::mackup::generate_custom_cfg() {
         items+=("$item")
     done
 
-    # 2. Auto-discover uncovered dot-dirs in $HOME.
+    # 2. Auto-discover uncovered dot-dirs.
     local name
     while IFS= read -r dotdir; do
         name="${dotdir##*/}"
-        # Skip if in the skip set.
         [[ "$skip_set" == *" $name "* ]] && continue
-        # Skip if already in backup.
         _in_backup "$name" && continue
-        # Skip if already in the curated list we built above.
         local dup=false
         for item in "${items[@]:-}"; do [[ "$item" == "$name" ]] && dup=true && break; done
         $dup && continue
@@ -87,24 +112,19 @@ ssr::mackup::generate_custom_cfg() {
     done < <(find "$HOME" -maxdepth 1 -mindepth 1 -name '.*' -type d 2>/dev/null | sort)
 
     if [[ ${#items[@]} -eq 0 ]]; then
-        ssr::log "No uncovered dot-dirs to add — ~/.mackup/ssr-custom.cfg not changed."
+        ssr::log "No uncovered dot-dirs — ~/.mackup/ssr-*.cfg unchanged."
         return 0
     fi
 
-    {
-        printf '# Auto-generated by ssr sync (%s)\n' "$(date '+%Y-%m-%dT%H:%M:%S')"
-        printf '# Do not edit manually — regenerated on every sync.\n'
-        printf '# Add custom paths via SSR_MACKUP_EXTRA_PATHS in ssr.conf.\n\n'
-        printf '[application]\n'
-        printf 'name = ssr-custom\n\n'
-        printf '[configuration_files]\n'
-        local it
+    local written=0 it
     for it in "${items[@]}"; do
-            printf '%s\n' "$it"
+        if _ssr_mackup_write_cfg "$cfg_dir" "$it"; then
+            written=$((written + 1))
+        fi
     done
-    } > "$cfg_file"
 
-    ssr::ok "~/.mackup/ssr-custom.cfg: ${#items[@]} item(s) added → ${items[*]}"
+    ssr::ok "~/.mackup/ssr-*.cfg: ${#items[@]} app definitions written (${written} new/updated)"
+    ssr::log "  → ${items[*]}"
 }
 
 ssr::mackup::ensure_installed() {