fix(toolset): 启动时自动补种系统工具集，工具集页面移至智能体侧边栏

- init_state_machine 启动时检查 DB 并补种 system_basic/system_chat/system_workflow
- 修复 postgres facade 缺少 is_system/category 参数的问题
- 前端工具集从"插件"独立为侧边栏"工具集"tab，位于智能体和插件之间

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

frontend/src/i18n/locales/en.json

@@ -10,6 +10,7 @@
     "workflow": "Workflow",
     "plugin": "Plugin",
     "agents": "Agents",
+    "toolsets": "Toolsets",
     "config": "Config",
     "logs": "Logs",
     "settings": "Settings"

frontend/src/i18n/locales/zh.json

@@ -10,6 +10,7 @@
     "workflow": "工作流",
     "plugin": "插件",
     "agents": "智能体",
+    "toolsets": "工具集",
     "config": "配置",
     "logs": "日志",
     "settings": "设置"