refact: remove feature plugin-framework (#15854)

* refact: remove feature plugin-framework

Signed-off-by: fufesou <linlong1266@gmail.com>

* refact: remove unused translations

Signed-off-by: fufesou <linlong1266@gmail.com>

* fix: delete settings tab observable with correct type

Signed-off-by: fufesou <linlong1266@gmail.com>

---------

Signed-off-by: fufesou <linlong1266@gmail.com>

src/lang/cn.rs

@@ -483,9 +483,6 @@ pub static ref T: std::collections::HashMap<&'static str, &'static str> =
         ("Fingerprint", "指纹"),
         ("Copy Fingerprint", "复制指纹"),
         ("no fingerprints", "没有指纹"),
-        ("Select a peer", "选择一个被控端"),
-        ("Select peers", "选择被控"),
-        ("Plugins", "插件"),
         ("Uninstall", "卸载"),
         ("Update", "更新"),
         ("Enable", "启用"),