feat(plugins): enable .bat/.py plugin discovery + HWPX format-handler plugin

plugins/format-handler/hwpx/manifest.json

@@ -0,0 +1,18 @@
+{
+  "name": "officecli-hwpx-py",
+  "version": "0.1.0",
+  "protocol": 1,
+  "kinds": ["format-handler"],
+  "extensions": [".hwpx"],
+  "runtime": "python",
+  "idle_timeout_seconds": { "default": 30, "verbs": { "save": 60, "dump": 30 } },
+  "vocabulary": {
+    "addable_types": ["paragraph", "section"],
+    "settable_props": {
+      "paragraph": ["text", "style"]
+    },
+    "path_segments": ["/section[N]", "/section[N]/paragraph[M]"]
+  },
+  "description": "Minimal HWPX format handler (Python)",
+  "supports": ["paragraphs"]
+}

plugins/format-handler/hwpx/plugin.bat

@@ -0,0 +1,19 @@
+@echo off
+REM OfficeCLI HWPX Plugin Wrapper
+REM This script runs the Python plugin
+
+setlocal
+
+set PYTHON_SCRIPT=%~dp0plugin.py
+set PYTHON=python
+
+if not exist "%PYTHON_SCRIPT%" (
+    echo Error: plugin.py not found at %PYTHON_SCRIPT%
+    exit /b 1
+)
+
+REM Pass all arguments to the Python script
+"%PYTHON%" "%PYTHON_SCRIPT%" %*
+
+endlocal
+exit /b %ERRORLEVEL%