fix(scripts): kimi skipped in --parallel, stale progress idx, --path multi-tool guard, rm -rf slug guard (#825)

Four install/convert bugs reported by @sunilkumarvalmiki (#817-#820), each
verified in a sandbox before and after the change.

- convert.sh --tool all --parallel silently skipped kimi: the parallel batch
  listed 11 tools and the sequential batch 2, so the 14th tool ran in neither
  (kimi output: 0 files vs 273 for every other tool). Add kimi to the parallel
  batch — it writes to its own integrations/kimi/<slug>/ dir so it is
  parallel-safe. (#817)
- The sequential batch's progress counter was hardcoded idx=8, stale from an
  older batch size, printing "aider (8/14)" instead of 12/14. Derive it from
  the parallel list length so it can never drift again; now prints 13/14 and
  14/14. Same root cause as #817. (#818)
- --path is a documented single-destination override; with several --tool
  values every tool resolved to the same directory and clobbered each other.
  Refuse --path with more than one tool. Deliberately NOT restricting the path
  itself: the override is the supported way to redirect installs (e.g. to a
  sandbox), and validating it against an expected dir would break that. (#819)
- clean_tool_output runs rm -rf on $OUT_DIR/$1. The tool name is validated
  upstream so this is not reachable today, but a plain-slug guard on $1 makes a
  future direct caller unable to steer it outside $OUT_DIR via "../" or "/".
  A prefix check would not do: "$OUT_DIR/../x" still starts with the prefix. (#820)

Fixes #817
Fixes #818
Fixes #819
Fixes #820

Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

scripts/convert.sh

@@ -614,6 +614,9 @@ HEREDOC
 # but never pruned stale output). Preserves the committed README.md — the only
 # tracked file under integrations/<tool>/ for conversion targets.
 clean_tool_output() {
+  # Defensive: tool names are plain slugs; refuse anything else so a future
+  # caller can never steer this rm -rf outside $OUT_DIR via "../" or "/".
+  [[ "$1" =~ ^[a-z0-9-]+$ ]] || { echo "ERROR: clean_tool_output: refusing non-slug tool name '$1'" >&2; return 1; }
   local dir="$OUT_DIR/$1"
   [[ -d "$dir" ]] || return 0
   find "$dir" -mindepth 1 -maxdepth 1 ! -name 'README.md' -exec rm -rf {} +
@@ -717,7 +720,7 @@ main() {
 
   if $use_parallel && [[ "$tool" == "all" ]]; then
     # Tools that write to separate dirs can run in parallel; buffer output so each tool's output stays together
-    local parallel_tools=(antigravity gemini-cli opencode cursor openclaw qwen zcode codex osaurus hermes vibe)
+    local parallel_tools=(antigravity gemini-cli opencode cursor openclaw qwen zcode kimi codex osaurus hermes vibe)
     local parallel_out_dir
     parallel_out_dir="$(mktemp -d)"
     info "Converting: ${#parallel_tools[@]}/${n_tools} tools in parallel (output buffered per tool)..."
@@ -729,7 +732,7 @@ main() {
       [[ -f "$parallel_out_dir/$t" ]] && cat "$parallel_out_dir/$t"
     done
     rm -rf "$parallel_out_dir"
-    local idx=8
+    local idx=$(( ${#parallel_tools[@]} + 1 ))
     for t in aider windsurf; do
       progress_bar "$idx" "$n_tools"
       printf "\n"

scripts/install.sh

@@ -1258,6 +1258,12 @@ main() {
       $duplicate || _cleaned+=("$_t")
     done
     _tool_list=("${_cleaned[@]}")
+    # --path is a single-destination override; with several tools every one of
+    # them would land in the same directory and clobber each other.
+    if [[ -n "$OVERRIDE_PATH" && ${#_tool_list[@]} -gt 1 ]]; then
+      err "--path sets ONE destination; use it with exactly one --tool (got ${#_tool_list[@]}: ${_tool_list[*]})."
+      exit 1
+    fi
   fi
 
   # Decide whether to show interactive UI