fix(convert): prune stale tool output before regenerating (#605)

convert.sh overwrote per-agent output in place but never removed files for
agents that were renamed or deleted, so orphans accumulated in the gitignored
integrations/<tool>/ dirs (e.g. agency-security-engineer lingered in
antigravity/ and openclaw/ long after the source agent was gone) — and install.sh
would happily copy them.

Add clean_tool_output(), called once at the top of run_conversions (the single
choke point for serial, parallel, and single-file paths): it wipes the tool's
generated output but preserves the committed README.md (the only tracked file
under integrations/<tool>/ for conversion targets).

Verified: antigravity regenerated to 232 (was 233), orphan pruned, README kept.

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

scripts/convert.sh

@@ -528,10 +528,22 @@ HEREDOC
 
 # --- Main loop ---
 
+# Remove a tool's previously-generated output before regenerating, so renamed or
+# deleted agents don't leave orphan files behind (convert.sh overwrites in place
+# but never pruned stale output). Preserves the committed README.md — the only
+# tracked file under integrations/<tool>/ for conversion targets.
+clean_tool_output() {
+  local dir="$OUT_DIR/$1"
+  [[ -d "$dir" ]] || return 0
+  find "$dir" -mindepth 1 -maxdepth 1 ! -name 'README.md' -exec rm -rf {} +
+}
+
 run_conversions() {
   local tool="$1"
   local count=0
 
+  clean_tool_output "$tool"
+
   for dir in "${AGENT_DIRS[@]}"; do
     local dirpath="$REPO_ROOT/$dir"
     [[ -d "$dirpath" ]] || continue