Add PreUp, PostUp, PreDown, PostDown for client (#1714)

* Fix create client popup background is not white

* Fix no Add button when client Allowed Ips or Server Allowed Ips is empty

* Add preUp preDown postUp postDown for client

* Add description of hooks for client config

* Move hooks's label text into 'hooks' in en.json

---------

Co-authored-by: yanghuanglin <yanghuanglin@qq.com>
Co-authored-by: Bernd Storath <999999bst@gmail.com>

src/server/database/migrations/meta/_journal.json

@@ -5,14 +5,14 @@
     {
       "idx": 0,
       "version": "6",
-      "when": 1739266828300,
+      "when": 1741331552405,
       "tag": "0000_short_skin",
       "breakpoints": true
     },
     {
       "idx": 1,
       "version": "6",
-      "when": 1739266837347,
+      "when": 1741331579259,
       "tag": "0001_classy_the_stranger",
       "breakpoints": true
     }