feat(i18n): add Indonesian (Bahasa Indonesia) language support (#1399)

- Add 'id' to Language type in translations.ts
- Add ~1000 Indonesian translation keys covering all UI sections
- Update LanguageContext to persist 'id' in localStorage
- Add ID button to Header.tsx language toggle
- Add �� option to HeaderBar.tsx desktop dropdown and mobile toggle
- Add Indonesian translations to inline text objects in
  LoginRequiredOverlay, StrategyMarketPage, PositionHistory

Closes #XX

web/src/components/HeaderBar.tsx

@@ -99,8 +99,8 @@ export default function HeaderBar({
             {(() => {
               // Define all navigation tabs
               const navTabs: { page: Page; path: string; label: string; requiresAuth: boolean }[] = [
-                { page: 'data', path: '/data', label: language === 'zh' ? '数据' : 'Data', requiresAuth: false },
-                { page: 'strategy-market', path: '/strategy-market', label: language === 'zh' ? '策略市场' : 'Market', requiresAuth: true },
+                { page: 'data', path: '/data', label: language === 'zh' ? '数据' : language === 'id' ? 'Data' : 'Data', requiresAuth: false },
+                { page: 'strategy-market', path: '/strategy-market', label: language === 'zh' ? '策略市场' : language === 'id' ? 'Pasar' : 'Market', requiresAuth: true },
                 { page: 'traders', path: '/traders', label: t('configNav', language), requiresAuth: true },
                 { page: 'trader', path: '/dashboard', label: t('dashboardNav', language), requiresAuth: true },
                 { page: 'strategy', path: '/strategy', label: t('strategyNav', language), requiresAuth: true },
@@ -259,7 +259,7 @@ export default function HeaderBar({
                 className="flex items-center gap-2 px-3 py-2 rounded transition-colors text-nofx-text-muted hover:bg-white/5"
               >
                 <span className="text-lg">
-                  {language === 'zh' ? '🇨🇳' : '🇺🇸'}
+                  {language === 'zh' ? '🇨🇳' : language === 'id' ? '🇮🇩' : '🇺🇸'}
                 </span>
                 <ChevronDown className="w-4 h-4" />
               </button>
@@ -288,6 +288,17 @@ export default function HeaderBar({
                     <span className="text-base">🇺🇸</span>
                     <span className="text-sm">English</span>
                   </button>
+                  <button
+                    onClick={() => {
+                      onLanguageChange?.('id')
+                      setLanguageDropdownOpen(false)
+                    }}
+                    className={`w-full flex items-center gap-2 px-3 py-2 transition-colors text-nofx-text-muted hover:text-white
+                      ${language === 'id' ? 'bg-nofx-gold/10' : 'hover:bg-white/5'}`}
+                  >
+                    <span className="text-base">🇮🇩</span>
+                    <span className="text-sm">Bahasa</span>
+                  </button>
                 </div>
               )}
             </div>
@@ -329,8 +340,8 @@ export default function HeaderBar({
               <div className="flex flex-col gap-6 mb-12">
                 {(() => {
                   const navTabs: { page: Page; path: string; label: string; requiresAuth: boolean }[] = [
-                    { page: 'data', path: '/data', label: language === 'zh' ? '数据' : 'Data', requiresAuth: false },
-                    { page: 'strategy-market', path: '/strategy-market', label: language === 'zh' ? '策略市场' : 'Market', requiresAuth: true },
+                    { page: 'data', path: '/data', label: language === 'zh' ? '数据' : language === 'id' ? 'Data' : 'Data', requiresAuth: false },
+                    { page: 'strategy-market', path: '/strategy-market', label: language === 'zh' ? '策略市场' : language === 'id' ? 'Pasar' : 'Market', requiresAuth: true },
                     { page: 'traders', path: '/traders', label: t('configNav', language), requiresAuth: true },
                     { page: 'trader', path: '/dashboard', label: t('dashboardNav', language), requiresAuth: true },
                     { page: 'strategy', path: '/strategy', label: t('strategyNav', language), requiresAuth: true },
@@ -429,7 +440,7 @@ export default function HeaderBar({
                 <div className="grid grid-cols-2 gap-4">
                   {/* Lang Switcher */}
                   <div className="flex bg-zinc-900 rounded-lg p-1 border border-zinc-800">
-                    {['zh', 'en'].map((lang) => (
+                    {['zh', 'en', 'id'].map((lang) => (
                       <button
                         key={lang}
                         onClick={() => {
@@ -441,7 +452,7 @@ export default function HeaderBar({
                           : 'text-zinc-500'
                           }`}
                       >
-                        {lang === 'zh' ? 'CN' : 'EN'}
+                        {lang === 'zh' ? 'CN' : lang === 'id' ? 'ID' : 'EN'}
                       </button>
                     ))}
                   </div>