feat: chat language display, disabled EntitySelect items, dev scripts

Chat language:
- Added language_code field to TelegramChat model + migration
- Saved from message.from.language_code on webhook/polling
- Displayed as badge on bot chat cards and target receiver items
- Resolved from DB in target API response (works for existing receivers)
- Shown in chat picker dropdown (desc includes language)

EntitySelect improvements:
- Tracker-target link selector shows all targets, already-linked ones
  appear disabled with "Already linked" hint
- Receiver chat picker shows already-added chats as disabled

Dev scripts:
- scripts/restart-backend.sh and restart-frontend.sh
- Updated .claude/docs/dev-servers.md to reference scripts

frontend/src/lib/i18n/en.json

@@ -176,6 +176,7 @@
 		"linkedTargets": "targets",
 		"noLinkedTargets": "No targets linked. Add a target below.",
 		"addTarget": "Add target",
+		"alreadyLinked": "Already linked",
 		"testBasic": "Send test message",
 		"testPeriodic": "Test periodic summary",
 		"testScheduled": "Test scheduled assets",

frontend/src/lib/i18n/ru.json

@@ -176,6 +176,7 @@
 		"linkedTargets": "получатели",
 		"noLinkedTargets": "Нет привязанных получателей. Добавьте получателя ниже.",
 		"addTarget": "Добавить получателя",
+		"alreadyLinked": "Уже привязан",
 		"testBasic": "Отправить тестовое сообщение",
 		"testPeriodic": "Тест периодической сводки",
 		"testScheduled": "Тест запланированных фото",

frontend/src/routes/bots/TelegramBotTab.svelte

@@ -306,6 +306,7 @@
 										<div class="flex items-center gap-2">
 											<span class="font-medium">{chat.title || chat.username || 'Unknown'}</span>
 											<span class="text-xs px-1.5 py-0.5 rounded bg-[var(--color-muted)] text-[var(--color-muted-foreground)]">{chatTypeLabel(chat.type)}</span>
+											{#if chat.language_code}<span class="text-xs px-1.5 py-0.5 rounded bg-[var(--color-muted)] text-[var(--color-muted-foreground)]">{chat.language_code.toUpperCase()}</span>{/if}
 											<span class="text-xs text-[var(--color-muted-foreground)] font-mono">{chat.chat_id}</span>
 										</div>
 										<div class="flex items-center gap-1">

frontend/src/routes/notification-trackers/+page.svelte

@@ -429,7 +429,7 @@
 						{tracker}
 						{trackingConfigs}
 						{templateConfigs}
-						unlinkedTargets={getUnlinkedTargets(tracker)}
+						unlinkedTargets={targets}
 						newLinkTargetId={newLinkTargetId[tracker.id] || 0}
 						newLinkTrackingConfigId={newLinkTrackingConfigId[tracker.id] || 0}
 						newLinkTemplateConfigId={newLinkTemplateConfigId[tracker.id] || 0}

frontend/src/routes/notification-trackers/LinkedTargetsSection.svelte

@@ -57,11 +57,14 @@
 
 	const trackingConfigItems = $derived(toItems(trackingConfigs));
 	const templateConfigItems = $derived(toItems(templateConfigs));
+	const linkedTargetIds = $derived(new Set((tracker.tracker_targets || []).map((tt: any) => tt.target_id)));
 	const targetItems = $derived<EntityItem[]>(unlinkedTargets.map(tgt => ({
 		value: tgt.id,
 		label: tgt.name,
 		icon: tgt.icon || (tgt.type === 'telegram' ? 'mdiSend' : 'mdiWebhook'),
 		desc: tgt.type,
+		disabled: linkedTargetIds.has(tgt.id),
+		disabledHint: linkedTargetIds.has(tgt.id) ? t('notificationTracker.alreadyLinked') : undefined,
 	})));
 </script>
 

frontend/src/routes/targets/+page.svelte

@@ -311,7 +311,19 @@
 		receiverSubmitting = true;
 		receiverHeadersError = '';
 		try {
-			const config = { ...receiverForm };
+			const config: Record<string, any> = { ...receiverForm };
+			// Enrich Telegram receiver with chat metadata
+			if (config.chat_id && addingReceiverForTarget) {
+				const target = allTargets.find(t => t.id === addingReceiverForTarget);
+				const botId = target?.config?.bot_id || target?.config?.telegram_bot_id;
+				if (botId && receiverBotChats[botId]) {
+					const chat = receiverBotChats[botId].find((c: any) => String(c.chat_id) === String(config.chat_id));
+					if (chat) {
+						config.chat_name = chat.title || chat.username || '';
+						if (chat.language_code) config.language_code = chat.language_code;
+					}
+				}
+			}
 			// Parse headers JSON for webhook
 			if ('headers' in config && typeof config.headers === 'string') {
 				if (config.headers) {
@@ -535,6 +547,9 @@
 							<div class="flex items-center gap-2 min-w-0">
 								<MdiIcon name={TYPE_ICONS[target.type] || 'mdiTarget'} size={14} />
 								<span class="text-sm truncate">{receiverLabel(target, recv)}</span>
+								{#if (recv as any).language_code || recv.config?.language_code}
+									<span class="text-xs px-1 py-0.5 rounded bg-[var(--color-muted)] text-[var(--color-muted-foreground)]">{((recv as any).language_code || recv.config.language_code).toUpperCase()}</span>
+								{/if}
 							</div>
 							<div class="flex items-center gap-1">
 								<IconButton icon="mdiSend" title={t('targets.test')}
@@ -563,11 +578,11 @@
 							{#if target.type === 'telegram'}
 								{@const botId = target.config?.bot_id}
 								{@const existingKeys = new Set((target.receivers || []).map((r: TargetReceiver) => r.receiver_key))}
-								{@const chatItems = (receiverBotChats[botId] || []).map((c: TelegramChat) => ({
+								{@const chatItems = (receiverBotChats[botId] || []).map((c: any) => ({
 									value: c.chat_id,
 									label: c.title || c.username || c.chat_id,
 									icon: c.type === 'private' ? 'mdiAccount' : c.type === 'channel' ? 'mdiBullhorn' : 'mdiAccountGroup',
-									desc: `${c.type} · ${c.chat_id}`,
+									desc: `${c.type}${c.language_code ? ' · ' + c.language_code.toUpperCase() : ''} · ${c.chat_id}`,
 									disabled: existingKeys.has(c.chat_id),
 									disabledHint: existingKeys.has(c.chat_id) ? t('targets.alreadyAdded') : undefined,
 								}))}