web: de-brand PhotoPrism references in user-facing copy

Replaces "PhotoPrism" in UI strings (empty states, tooltips, toasts,
log header, login screen) with neutral terms like "the indexer", "the
library", "the server" — accurate regardless of backend. The login
header becomes "Mulimage" and drops the explicit PhotoPrism mention.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

web/src/lib/components/layout/SettingsDialog.svelte

@@ -142,7 +142,7 @@
 						Library settings
 					</Dialog.Title>
 					<Dialog.Description class="mt-1 text-xs text-muted-foreground">
-						Drive PhotoPrism's library, indexer, importer and server log.
+						Drive the library, indexer, importer and server log.
 					</Dialog.Description>
 				</div>
 				<Dialog.Close
@@ -403,8 +403,8 @@
 				<Tabs.Content value="logs" class="space-y-2 text-[12px] outline-none">
 					<div class="flex items-center justify-between">
 						<p class="text-muted-foreground">
-							Most recent PhotoPrism errors and warnings. Auto-refreshes
-							every 5 seconds.
+							Most recent server errors and warnings. Auto-refreshes every
+							5 seconds.
 						</p>
 						<button
 							type="button"