fix: rename init() to register() for OpenClaw plugin API

OpenClaw expects 'register' or 'activate' export, not 'init'

index.js

@@ -11,8 +11,8 @@ const {
   SlashCommandHandler
 } = require('./safe-restart/dist/index.js');
 
-// Plugin initialization function
-function init(api, config) {
+// Plugin registration function (OpenClaw expects 'register' or 'activate')
+function register(api, config) {
   const logger = api.logger || { info: console.log, error: console.error };
   
   logger.info('PaddedCell plugin initializing...');
@@ -63,7 +63,7 @@ function init(api, config) {
 }
 
 // Export for OpenClaw
-module.exports = { init };
+module.exports = { register };
 
 // Also export individual modules for direct use
 module.exports.pcexec = pcexec;