feat: test menu dropdown, split text/media messages, target settings, provider URL links

- Replace 3 test buttons with unified dropdown menu (basic/periodic/scheduled/memory)
- Send text message first, then assets as reply (not combined caption+media)
- Pass all target config settings to Telegram client (disable_url_preview, max_media, chunk_delay, etc.)
- Real data test notifications for periodic/scheduled/memory (fetch from Immich)
- Provider card URL is now a clickable hyperlink
- Localized test type labels (EN/RU)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

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

@@ -161,7 +161,9 @@
 								<p class="font-medium">{provider.name}</p>
 								<span class="text-xs px-1.5 py-0.5 rounded bg-[var(--color-muted)] text-[var(--color-muted-foreground)]">{provider.type}</span>
 							</div>
-							<p class="text-xs text-[var(--color-muted-foreground)] font-mono">{provider.config?.url || ''}</p>
+							{#if provider.config?.url}
+								<a href={provider.config.url} target="_blank" rel="noopener" class="text-xs text-[var(--color-muted-foreground)] font-mono hover:text-[var(--color-primary)] hover:underline">{provider.config.url}</a>
+							{/if}
 						</div>
 					</div>
 					<div class="flex items-center gap-1">