feat: Discord/Slack/ntfy/Matrix targets, command templates, delete protection, email/matrix bots

- Discord, Slack, ntfy, Matrix notification target types with clients and dispatch
- MatrixBot model + API + frontend in Bots tab
- Command template system fully wired into all handler commands
- Default command templates seeded (EN/RU, 14 slots each)
- Command template editor with variables reference including child fields
- Delete protection on all 10 entity types (409 with consumer details)
- Provider type selector on template config forms
- Target type selector as dropdown with all 7 types
- Response template selector on command config form
- CLAUDE.md: mandatory server restart rule, child properties rule

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

@@ -13,6 +13,7 @@
 	import { snackSuccess, snackError } from '$lib/stores/snackbar.svelte';
 
 	let configs = $state<any[]>([]);
+	let cmdTemplateConfigs = $state<any[]>([]);
 	let loaded = $state(false);
 	let showForm = $state(false);
 	let editing = $state<number | null>(null);
@@ -46,13 +47,17 @@
 		response_mode: 'media',
 		default_count: 5,
 		rate_limits: { search: 30, default: 10 },
+		command_template_config_id: null as number | null,
 	});
 	let form = $state(defaultForm());
 
 	onMount(load);
 	async function load() {
 		try {
-			configs = await api('/command-configs');
+			[configs, cmdTemplateConfigs] = await Promise.all([
+				api('/command-configs'),
+				api('/command-template-configs'),
+			]);
 		} catch (err: any) { error = err.message || t('common.loadError'); snackError(error); }
 		finally { loaded = true; }
 	}
@@ -68,6 +73,7 @@
 			response_mode: cfg.response_mode || 'media',
 			default_count: cfg.default_count || 5,
 			rate_limits: { search: cfg.rate_limits?.search || 30, default: cfg.rate_limits?.default || 10 },
+			command_template_config_id: cfg.command_template_config_id || null,
 		};
 		editing = cfg.id;
 		showForm = true;
@@ -157,6 +163,17 @@
 				</div>
 			</div>
 
+			<div>
+				<label for="cc-template" class="block text-sm font-medium mb-1">{t('commandConfig.responseTemplate')}</label>
+				<select id="cc-template" bind:value={form.command_template_config_id}
+					class="w-full px-3 py-2 border border-[var(--color-border)] rounded-md text-sm bg-[var(--color-background)]">
+					<option value={null}>— {t('commandConfig.noTemplate')} —</option>
+					{#each cmdTemplateConfigs.filter((c: any) => c.provider_type === form.provider_type) as tpl}
+						<option value={tpl.id}>{tpl.name}{tpl.user_id === 0 ? ' (System)' : ''}</option>
+					{/each}
+				</select>
+			</div>
+
 			<div class="grid grid-cols-2 sm:grid-cols-4 gap-3">
 				<div>
 					<label class="block text-xs mb-1">{t('commandConfig.locale')}</label>