Add i18n support (en/zh) with Paraglide JS (#12)

Integrate Paraglide JS for compile-time i18n with URL-based locale routing.
All ~226 UI strings across 34+ route/component files are translated. Better Auth UI
gets Chinese localization via AuthUIProvider's localization prop.

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: dengzhaofun

apps/admin/.gitignore

@@ -14,3 +14,6 @@ todos.json
 
 # Generated by @tanstack/router-plugin on vite dev/build
 src/routeTree.gen.ts
+
+# Generated by @inlang/paraglide-js
+src/paraglide/

apps/admin/messages/en.json

@@ -0,0 +1,228 @@
+{
+  "apikeys_title": "API Keys",
+  "apikeys_admin_keys": "Admin Keys",
+  "apikeys_client_credentials": "Client Credentials",
+  "apikeys_create_admin_key": "Create Admin Key",
+  "apikeys_create_credential": "Create Credential",
+  "apikeys_admin_keys_desc": "Server-to-server API keys for admin access. Keep these secret.",
+  "apikeys_client_credentials_desc": "Client credentials for C-end access with HMAC identity verification.",
+  "apikeys_no_admin_keys": "No admin keys yet.",
+  "apikeys_no_credentials": "No client credentials yet.",
+  "apikeys_expires": "Expires",
+  "apikeys_publishable_key": "Publishable Key",
+  "apikeys_dev_mode": "Dev Mode",
+  "apikeys_delete_admin_key_title": "Delete Admin Key?",
+  "apikeys_delete_admin_key_desc": "This will permanently delete the key. Any services using it will lose access.",
+  "apikeys_delete_credential_title": "Delete Credential?",
+  "apikeys_delete_credential_desc": "This will permanently delete the credential. Any clients using it will lose access.",
+  "apikeys_credential_created_title": "Client Credential Created",
+  "apikeys_credential_created_desc": "Copy both keys now. The secret will not be shown again.",
+  "apikeys_admin_key_created_title": "Admin Key Created",
+  "apikeys_admin_key_created_desc": "Copy this key now. It will not be shown again.",
+  "apikeys_failed_to_load_keys": "Failed to load keys:",
+  "apikeys_failed_to_load_credentials": "Failed to load credentials:",
+  "checkin_title": "Check-in Configs",
+  "checkin_new_config": "New Config",
+  "checkin_new_checkin_config": "New Check-in Config",
+  "checkin_config_created": "Config created successfully",
+  "checkin_config_deleted": "Config deleted",
+  "checkin_config_updated": "Config updated",
+  "checkin_failed_create_config": "Failed to create config",
+  "checkin_failed_delete_config": "Failed to delete config",
+  "checkin_failed_update_config": "Failed to update config",
+  "checkin_failed_load_configs": "Failed to load configs:",
+  "checkin_checkin_users": "Check-in Users",
+  "checkin_reset_mode": "Reset Mode",
+  "checkin_reset_none": "None (cumulative)",
+  "checkin_reset_weekly": "Weekly",
+  "checkin_reset_monthly": "Monthly",
+  "checkin_week_starts_on": "Week Starts On",
+  "checkin_sunday": "Sunday",
+  "checkin_monday": "Monday",
+  "checkin_tuesday": "Tuesday",
+  "checkin_wednesday": "Wednesday",
+  "checkin_thursday": "Thursday",
+  "checkin_friday": "Friday",
+  "checkin_saturday": "Saturday",
+  "checkin_target": "Target",
+  "checkin_timezone": "Timezone",
+  "checkin_target_progress": "Target Progress",
+  "checkin_days": "days",
+  "checkin_cycle_days": "Cycle Days",
+  "checkin_total_days": "Total Days",
+  "checkin_current_streak": "Current Streak",
+  "checkin_longest_streak": "Longest Streak",
+  "checkin_already_checked_in": "Already checked in",
+  "checkin_new_checkin": "New check-in",
+  "checkin_completed": "Completed",
+  "checkin_no_target": "No target",
+  "checkin_remaining": "Remaining",
+  "checkin_cycle_key": "Cycle Key",
+  "checkin_full_user_state": "Full User State",
+  "checkin_last_checkin_date": "Last Check-in Date",
+  "checkin_last_checkin_at": "Last Check-in At",
+  "checkin_first_checkin_at": "First Check-in At",
+  "checkin_config_id": "Config ID",
+  "checkin_end_user_id": "End User ID",
+  "checkin_organization_id": "Organization ID",
+  "checkin_history_count": "History ({count} calls)",
+  "checkin_duplicate": "duplicate",
+  "checkin_new": "new",
+  "checkin_already_checked_in_today": "Already checked in today",
+  "checkin_checkin_target_completed": "Check-in successful — target completed!",
+  "checkin_checkin_successful": "Check-in successful!",
+  "checkin_checkin_failed": "Check-in failed",
+  "checkin_preview_test": "Preview & Test",
+  "checkin_test_user": "Test User",
+  "checkin_test_user_desc": "Using your admin account as the test end-user",
+  "checkin_user_id": "User ID",
+  "checkin_email": "Email",
+  "checkin_check_in": "Check In",
+  "checkin_checking_in": "Checking in...",
+  "checkin_latest_result": "Latest Result",
+  "checkin_clear": "Clear",
+  "checkin_target_just_completed": "Target just completed!",
+  "checkin_checkin_config": "Check-in Config",
+  "checkin_preview_config": "Preview: {name}",
+  "common_loading": "Loading...",
+  "common_saving": "Saving...",
+  "common_error": "Error",
+  "common_back": "Back",
+  "common_create": "Create",
+  "common_edit": "Edit",
+  "common_delete": "Delete",
+  "common_cancel": "Cancel",
+  "common_save_changes": "Save Changes",
+  "common_done": "Done",
+  "common_copy": "Copy",
+  "common_copied": "Copied!",
+  "common_active": "Active",
+  "common_inactive": "Inactive",
+  "common_status": "Status",
+  "common_created": "Created",
+  "common_updated": "Updated",
+  "common_name": "Name",
+  "common_alias": "Alias",
+  "common_description": "Description",
+  "common_actions": "Actions",
+  "common_unlimited": "Unlimited",
+  "common_deleting": "Deleting...",
+  "common_failed_to_load": "Failed to load {resource}: {error}",
+  "common_no_items_yet": "No {resource} yet.",
+  "common_revoke": "Revoke",
+  "common_type": "Type",
+  "common_icon": "Icon",
+  "common_sort_order": "Sort Order",
+  "common_dash": "—",
+  "dashboard_title": "Dashboard",
+  "dashboard_welcome": "Welcome, {name}",
+  "dashboard_welcome_default": "Welcome",
+  "dashboard_signed_in_as": "Signed in as",
+  "exchange_title": "Exchange Configs",
+  "exchange_new_config": "New Config",
+  "exchange_new_exchange_config": "New Exchange Config",
+  "exchange_config_created": "Exchange config created successfully",
+  "exchange_config_deleted": "Config deleted",
+  "exchange_failed_create_config": "Failed to create config",
+  "exchange_failed_load_configs": "Failed to load configs:",
+  "exchange_options": "Exchange Options",
+  "exchange_new_option": "New Option",
+  "exchange_new_exchange_option": "New Exchange Option",
+  "exchange_option_created": "Exchange option created successfully",
+  "exchange_option_deleted": "Option deleted",
+  "exchange_failed_create_option": "Failed to create option",
+  "exchange_failed_update_option": "Failed to update option",
+  "exchange_failed_delete_option": "Failed to delete option",
+  "exchange_failed_load_definitions": "Failed to load definitions",
+  "exchange_no_options": "No exchange options yet.",
+  "exchange_no_configs": "No exchange configurations yet.",
+  "exchange_costs": "Costs",
+  "exchange_rewards": "Rewards",
+  "exchange_cost_items": "Cost Items",
+  "exchange_reward_items": "Reward Items",
+  "exchange_usage": "Usage",
+  "exchange_items_suffix": "item(s)",
+  "exchange_user_limit": "User Limit",
+  "exchange_global_limit": "Global Limit",
+  "exchange_execute_test": "Execute Test",
+  "exchange_execute": "Execute",
+  "exchange_executing": "Executing...",
+  "exchange_exchange_deleted": "Exchange deleted",
+  "item_items": "Items",
+  "item_definitions": "Definitions",
+  "item_categories": "Categories",
+  "item_new_definition": "New Definition",
+  "item_new_category": "New Category",
+  "item_item_tools": "Item Tools",
+  "item_inventory_lookup": "Inventory Lookup",
+  "item_grant_deduct": "Grant / Deduct Items",
+  "item_definition_created": "Item definition created successfully",
+  "item_definition_deleted": "Definition deleted",
+  "item_definition_updated": "Definition updated",
+  "item_category_created": "Category created successfully",
+  "item_category_deleted": "Category deleted",
+  "item_category_updated": "Category updated",
+  "item_failed_create_definition": "Failed to create item definition",
+  "item_failed_delete_definition": "Failed to delete definition",
+  "item_failed_create_category": "Failed to create category",
+  "item_failed_delete_category": "Failed to delete category",
+  "item_delete_definition_desc": "This will permanently delete this item definition and all inventory data associated with it.",
+  "item_delete_category_desc": "This will permanently delete this category. Item definitions using this category will become uncategorized.",
+  "item_unlimited_currency": "Unlimited (currency)",
+  "item_non_stackable": "Non-stackable",
+  "item_stackable": "Stackable",
+  "item_stack_limit": "Stack limit: {limit}",
+  "item_stack_lte": "Stack ≤ {limit}",
+  "item_hold_limit": "Hold Limit",
+  "item_no_categories": "No categories yet.",
+  "item_failed_load_definitions": "Failed to load definitions:",
+  "item_failed_load_categories": "Failed to load categories:",
+  "item_end_user_id": "End User ID",
+  "item_end_user_id_required": "End User ID is required",
+  "item_source": "Source",
+  "item_source_id": "Source ID (optional)",
+  "item_source_id_placeholder": "Optional idempotency key",
+  "item_grant": "Grant",
+  "item_deduct": "Deduct",
+  "item_grant_items": "Grant Items",
+  "item_granting": "Granting...",
+  "item_deduct_items": "Deduct Items",
+  "item_deducting": "Deducting...",
+  "item_failed_grant": "Failed to grant items",
+  "item_failed_deduct": "Failed to deduct items",
+  "item_add_item": "Add Item",
+  "item_add_valid_item": "Add at least one item with a valid definition",
+  "item_qty": "Qty",
+  "item_look_up": "Look Up",
+  "item_no_inventory": "No items in inventory.",
+  "item_quantity": "Quantity",
+  "item_stacks": "Stacks",
+  "marketing_hero_title": "Start simple, ship quickly.",
+  "marketing_hero_description": "This base starter intentionally keeps things light: two routes, clean structure, and the essentials you need to build from scratch.",
+  "marketing_feature_routing_title": "Type-Safe Routing",
+  "marketing_feature_routing_desc": "Routes and links stay in sync across every page.",
+  "marketing_feature_server_title": "Server Functions",
+  "marketing_feature_server_desc": "Call server code from your UI without creating API boilerplate.",
+  "marketing_feature_streaming_title": "Streaming by Default",
+  "marketing_feature_streaming_desc": "Ship progressively rendered responses for faster experiences.",
+  "marketing_feature_tailwind_title": "Tailwind Native",
+  "marketing_feature_tailwind_desc": "Design quickly with utility-first styling and reusable tokens.",
+  "marketing_about_title": "About ApolloKit",
+  "marketing_about_description": "ApolloKit is a game SaaS platform built with TanStack Start, Hono, and Better Auth.",
+  "marketing_footer_author": "Your name here",
+  "marketing_footer_rights": "All rights reserved",
+  "marketing_footer_built_with": "Built with TanStack Start",
+  "nav_brand": "ApolloKit",
+  "nav_sign_in": "Sign In",
+  "nav_home": "Home",
+  "nav_dashboard": "Dashboard",
+  "nav_about": "About",
+  "nav_navigation": "Navigation",
+  "nav_admin": "Admin",
+  "nav_checkin": "Check-in",
+  "nav_item": "Item",
+  "nav_exchange": "Exchange",
+  "nav_api_keys": "API Keys",
+  "nav_go_to_dashboard": "Go to Dashboard",
+  "nav_about_starter": "About This Starter"
+}