refactor: resolve() internal links instead of plain hrefs

Type-checks every link against the real route tree. Caught a dead one: the
book page linked tags to /tag/{id}, a route that has never existed.

frontend/src/lib/components/layout/search-form.svelte

@@ -1,4 +1,5 @@
 <script lang="ts">
+	import { resolve } from '$app/paths';
 	import * as Command from '$lib/components/ui/command/index';
 	import * as Kbd from '$lib/components/ui/kbd/index.js';
 	import * as InputGroup from '$lib/components/ui/input-group/index.js';
@@ -97,7 +98,7 @@
 						<Command.Item
 							value={String(book.id)}
 							onSelect={() => {
-								goto(`/book/${book.id}`);
+								goto(resolve('/(root)/(library)/book/[bookId]', { bookId: String(book.id) }));
 								open = false;
 							}}
 							class="cursor-pointer"
@@ -115,7 +116,9 @@
 											by
 											{#each book.authors as author}
 												<a
-													href="/library/{libraryState.activeLibrary!.id}/view?authors={author.id}"
+													href="{resolve('/(root)/(library)/library/[libraryId]/view', {
+														libraryId: String(libraryState.activeLibrary!.id)
+													})}?authors={author.id}"
 													class="cs-list hover:underline">{author.name}</a
 												> &thinsp;
 											{/each}