feat(komga): add Komga read-status sync with reports and history

Adds Komga sync feature to import read status from a Komga server.
Books are matched by title (case-insensitive) with series+title primary
match and title-only fallback. Sync reports are persisted with matched,
newly marked, and unmatched book lists. UI shows check icon for newly
marked books, sorted to top. Credentials (URL+username) are saved
between sessions. Uses HashSet for O(1) lookups to handle large libraries.

Closes #2

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/backoffice/lib/api.ts

@@ -539,3 +539,48 @@ export async function markSeriesRead(seriesName: string, status: "read" | "unrea
     body: JSON.stringify({ series: seriesName, status }),
   });
 }
+
+export type KomgaSyncRequest = {
+  url: string;
+  username: string;
+  password: string;
+};
+
+export type KomgaSyncResponse = {
+  id: string;
+  komga_url: string;
+  total_komga_read: number;
+  matched: number;
+  already_read: number;
+  newly_marked: number;
+  matched_books: string[];
+  newly_marked_books: string[];
+  unmatched: string[];
+  created_at: string;
+};
+
+export type KomgaSyncReportSummary = {
+  id: string;
+  komga_url: string;
+  total_komga_read: number;
+  matched: number;
+  already_read: number;
+  newly_marked: number;
+  unmatched_count: number;
+  created_at: string;
+};
+
+export async function syncKomga(req: KomgaSyncRequest) {
+  return apiFetch<KomgaSyncResponse>("/komga/sync", {
+    method: "POST",
+    body: JSON.stringify(req),
+  });
+}
+
+export async function listKomgaReports() {
+  return apiFetch<KomgaSyncReportSummary[]>("/komga/reports");
+}
+
+export async function getKomgaReport(id: string) {
+  return apiFetch<KomgaSyncResponse>(`/komga/reports/${id}`);
+}