feat: locale-aware command templates, debounced auto-sync, entity pickers

- Locale-aware templates: CommandTemplateSlot now has a locale column,
  allowing each slot to have per-language variants (EN/RU). Templates
  are resolved at runtime from the Telegram user's language_code.

- Merged system configs: "Default Commands (EN)" and "(RU)" merged
  into a single "Default Commands" config with locale-aware slots.
  Migration handles existing data automatically.

- Configurable command descriptions: hardcoded COMMAND_DESCRIPTIONS
  replaced with desc_* template slots (desc_status, desc_help, etc.)
  that users can customize per locale. setMyCommands registers all
  locales explicitly.

- Removed locale from CommandConfig: no longer needed since locale
  is derived from the Telegram user's language at runtime.

- Debounced command auto-sync: after command config/tracker changes,
  affected bots are marked dirty and synced after a 30s debounce
  window. Manual "Sync with Telegram" button still works.

- Entity pickers in LinkedTargetsSection: replaced 6 plain <select>
  elements with EntitySelect components (search, icons, keyboard nav).
  Added onselect callback and size="sm" props to EntitySelect.

frontend/src/routes/command-template-configs/+page.svelte

@@ -26,7 +26,7 @@
 		name: string;
 		description: string;
 		icon: string;
-		slots: Record<string, string>;
+		slots: Record<string, Record<string, string>>;
 		created_at: string;
 	}
 
@@ -35,6 +35,8 @@
 		description: string;
 	}
 
+	const LOCALES = ['en', 'ru'] as const;
+
 	let configs = $state<CmdTemplateConfig[]>([]);
 	let loaded = $state(false);
 	let showForm = $state(false);
@@ -48,6 +50,7 @@
 	let validateTimers: Record<string, ReturnType<typeof setTimeout>> = {};
 	let varsRef = $state<Record<string, any>>({});
 	let showVarsFor = $state<string | null>(null);
+	let activeLocale = $state<string>('en');
 
 	// Provider capabilities
 	let allCapabilities = $state<Record<string, any>>({});
@@ -61,10 +64,21 @@
 		name: '',
 		description: '',
 		icon: '',
-		slots: {} as Record<string, string>,
+		slots: {} as Record<string, Record<string, string>>,
 	});
 	let form = $state(defaultForm());
 
+	/** Get slot template for current locale, with fallback. */
+	function getSlotValue(slotName: string): string {
+		return form.slots[slotName]?.[activeLocale] || '';
+	}
+
+	/** Set slot template for current locale. */
+	function setSlotValue(slotName: string, value: string) {
+		if (!form.slots[slotName]) form.slots[slotName] = {};
+		form.slots[slotName][activeLocale] = value;
+	}
+
 	onMount(load);
 
 	async function load() {
@@ -122,7 +136,7 @@
 
 	function refreshAllPreviews() {
 		for (const slot of commandSlots) {
-			const template = form.slots[slot.name] || '';
+			const template = getSlotValue(slot.name);
 			if (template) validateSlot(slot.name, template, true);
 		}
 	}
@@ -131,20 +145,27 @@
 		form = defaultForm();
 		editing = null;
 		showForm = true;
+		activeLocale = 'en';
 		slotPreview = {};
 		slotErrors = {};
 	}
 
 	function edit(c: CmdTemplateConfig) {
+		// Deep copy nested slots
+		const slotsCopy: Record<string, Record<string, string>> = {};
+		for (const [k, v] of Object.entries(c.slots)) {
+			slotsCopy[k] = { ...v };
+		}
 		form = {
 			provider_type: c.provider_type,
 			name: c.name,
 			description: c.description || '',
 			icon: c.icon || '',
-			slots: { ...c.slots },
+			slots: slotsCopy,
 		};
 		editing = c.id;
 		showForm = true;
+		activeLocale = 'en';
 		slotPreview = {};
 		slotErrors = {};
 		setTimeout(() => refreshAllPreviews(), 100);
@@ -170,15 +191,20 @@
 	}
 
 	function clone(c: CmdTemplateConfig) {
+		const slotsCopy: Record<string, Record<string, string>> = {};
+		for (const [k, v] of Object.entries(c.slots)) {
+			slotsCopy[k] = { ...v };
+		}
 		form = {
 			provider_type: c.provider_type,
 			name: `${c.name} (Copy)`,
 			description: c.description || '',
 			icon: c.icon || '',
-			slots: { ...c.slots },
+			slots: slotsCopy,
 		};
 		editing = null;
 		showForm = true;
+		activeLocale = 'en';
 		slotPreview = {};
 		slotErrors = {};
 		setTimeout(() => refreshAllPreviews(), 100);
@@ -245,8 +271,20 @@
 
 		<fieldset class="border border-[var(--color-border)] rounded-md p-3">
 			<legend class="text-sm font-medium px-1">{t('cmdTemplateConfig.commandResponses')}</legend>
-			<p class="text-xs text-[var(--color-muted-foreground)] mb-3">{t('cmdTemplateConfig.commandResponsesHint')}</p>
-			<div class="space-y-3 mt-2">
+			<p class="text-xs text-[var(--color-muted-foreground)] mb-2">{t('cmdTemplateConfig.commandResponsesHint')}</p>
+
+			<!-- Locale tabs -->
+			<div class="flex gap-1 mb-3 border-b border-[var(--color-border)]">
+				{#each LOCALES as loc}
+					<button type="button"
+						class="px-3 py-1.5 text-xs font-medium rounded-t-md transition-colors {activeLocale === loc ? 'bg-[var(--color-primary)] text-[var(--color-primary-foreground)]' : 'text-[var(--color-muted-foreground)] hover:bg-[var(--color-muted)]'}"
+						onclick={() => { activeLocale = loc; refreshAllPreviews(); }}>
+						{loc.toUpperCase()}
+					</button>
+				{/each}
+			</div>
+
+			<div class="space-y-3">
 				{#each commandSlots as slot}
 					<div>
 						<div class="flex items-center justify-between mb-1">
@@ -257,8 +295,8 @@
 							{/if}
 						</div>
 						<JinjaEditor
-							value={form.slots[slot.name] || ''}
-							onchange={(v: string) => { form.slots[slot.name] = v; validateSlot(slot.name, v); }}
+							value={getSlotValue(slot.name)}
+							onchange={(v: string) => { setSlotValue(slot.name, v); validateSlot(slot.name, v); }}
 							rows={3}
 							errorLine={slotErrorLines[slot.name] || null}
 						/>