fix(plugin): fix reloadp command not taking effect

- Use write_plugin_config() instead of directly modifying plugin_config dict
- Add remove_plugin_config() to clear plugin config before reload
- Update plugins to use pconf() and write_plugin_config() for better config management

plugins/linkai/linkai.py

@@ -289,7 +289,7 @@ class LinkAI(Plugin):
                     plugin_conf = json.load(f)
                     plugin_conf["midjourney"]["enabled"] = False
                     plugin_conf["summary"]["enabled"] = False
-                    plugin_config["linkai"] = plugin_conf
+                    write_plugin_config({"linkai": plugin_conf})
                     return plugin_conf
         except Exception as e:
             logger.exception(e)