settings: Clean schemas and types used for group settings.

Removed "type"/"Type" from schema and type names used
for group settings because we want to use "type"/"Type"
only for "type of a type" cases.

So, this commit renames-
- anonymous_group_type => anonymous_group_schema
- group_setting_type_schema => group_setting_value_schema
- GroupSettingType => GroupSettingValue

We also had duplicate definitions for GroupSettingType, in
state_data.ts and in settings_components.ts. So, removed it
from settings_components.ts.

web/src/user_groups.ts

@@ -9,7 +9,7 @@ import {page_params} from "./page_params";
 import * as settings_config from "./settings_config";
 import type {
     GroupPermissionSetting,
-    GroupSettingType,
+    GroupSettingValue,
     StateData,
     user_group_schema,
 } from "./state_data";
@@ -325,7 +325,7 @@ export function is_user_in_group(user_group_id: number, user_id: number): boolea
 }
 
 export function is_user_in_setting_group(
-    setting_group: GroupSettingType,
+    setting_group: GroupSettingValue,
     user_id: number,
 ): boolean {
     if (typeof setting_group === "number") {