refactor(i18n): modularize and shard by feature (#7134)

* refactor(i18n): move locale files to specific directories

Prepare for sharding up of locale resources by moving each locale into
its own directory. Use this as the base to manage future growth and
expansion of locale resources to cover most text in FormSG.

No code change.

* refactor(i18n): add features dir, shard login locale

Hold feature-specific locale resources in a `features/` dir for each
locale, to minimise clutter even as we add more text to hold as
resources.

* refactor(i18n): reorg translations by feature, not locale

frontend/src/i18n/locales/en-sg.ts

@@ -1,22 +1,10 @@
+import { enSG as login } from './features/login'
 import Translation from './types'
 
 export const enSG: Translation = {
   translation: {
     features: {
-      login: {
-        LoginPage: {
-          slogan: 'Build secure government forms in minutes',
-        },
-        components: {
-          LoginForm: {
-            onlyAvailableForPublicOfficers:
-              'Log in with a .gov.sg or other whitelisted email address',
-            emailEmptyErrorMsg: 'Please enter an email address',
-            login: 'Log in',
-            haveAQuestion: 'Have a question?',
-          },
-        },
-      },
+      login,
     },
   },
 }

frontend/src/i18n/locales/features/login/en-sg.ts

@@ -0,0 +1,16 @@
+import { Login } from '.'
+
+export const enSG: Login = {
+  LoginPage: {
+    slogan: 'Build secure government forms in minutes',
+  },
+  components: {
+    LoginForm: {
+      onlyAvailableForPublicOfficers:
+        'Log in with a .gov.sg or other whitelisted email address',
+      emailEmptyErrorMsg: 'Please enter an email address',
+      login: 'Log in',
+      haveAQuestion: 'Have a question?',
+    },
+  },
+}

frontend/src/i18n/locales/features/login/index.ts

@@ -0,0 +1,16 @@
+export * from './en-sg'
+export * from './zh-sg'
+
+export interface Login {
+  components: {
+    LoginForm: {
+      onlyAvailableForPublicOfficers: string
+      emailEmptyErrorMsg: string
+      login: string
+      haveAQuestion: string
+    }
+  }
+  LoginPage: {
+    slogan: string
+  }
+}

frontend/src/i18n/locales/features/login/zh-sg.ts

@@ -0,0 +1,16 @@
+import { Login } from '.'
+
+export const zhSG: Login = {
+  LoginPage: {
+    slogan: '在几分钟内创建安全的政府表格',
+  },
+  components: {
+    LoginForm: {
+      onlyAvailableForPublicOfficers:
+        '只供拥有 gov.sg 或其他列入白名单的电子邮件的公职人员使用',
+      emailEmptyErrorMsg: '请输入电子邮件地址',
+      login: '登录',
+      haveAQuestion: '有问题？',
+    },
+  },
+}

frontend/src/i18n/locales/types.ts

@@ -1,19 +1,9 @@
+import { Login } from './features/login'
+
 interface Translation {
   translation: {
     features: {
-      login: {
-        components: {
-          LoginForm: {
-            onlyAvailableForPublicOfficers: string
-            emailEmptyErrorMsg: string
-            login: string
-            haveAQuestion: string
-          }
-        }
-        LoginPage: {
-          slogan: string
-        }
-      }
+      login: Login
     }
   }
 }

frontend/src/i18n/locales/zh-sg.ts

@@ -1,22 +1,10 @@
+import { zhSG as login } from './features/login'
 import Translation from './types'
 
 export const zhSG: Translation = {
   translation: {
     features: {
-      login: {
-        LoginPage: {
-          slogan: '在几分钟内创建安全的政府表格',
-        },
-        components: {
-          LoginForm: {
-            onlyAvailableForPublicOfficers:
-              '只供拥有 gov.sg 或其他列入白名单的电子邮件的公职人员使用',
-            emailEmptyErrorMsg: '请输入电子邮件地址',
-            login: '登录',
-            haveAQuestion: '有问题？',
-          },
-        },
-      },
+      login,
     },
   },
 }