feat: add two-digit counter suffix to vpn-configs dir (CN_YYYY-MM-DD_NN)

openvpncertupdate.py

@@ -271,7 +271,16 @@ def build_ovpn(
     template_content = Path(template_path).read_text()
     inline_content   = Path(inline_path).read_text()
     today = date.today().strftime("%Y-%m-%d")
-    out_dir = Path(output_base_dir) / f"{cn}_{today}"
+    prefix = f"{cn}_{today}_"
+    base = Path(output_base_dir)
+    existing = [
+        int(d.name[len(prefix):])
+        for d in base.iterdir()
+        if d.is_dir() and d.name.startswith(prefix)
+        and d.name[len(prefix):].isdigit() and len(d.name[len(prefix):]) == 2
+    ] if base.exists() else []
+    next_n = max(existing) + 1 if existing else 0
+    out_dir = base / f"{prefix}{next_n:02d}"
     out_dir.mkdir(parents=True, exist_ok=True)
     out_file = out_dir / config_name
     out_file.write_text(template_content + "\n" + inline_content)