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/api/src/error.rs

@@ -83,3 +83,9 @@ impl From<std::io::Error> for ApiError {
         Self::internal(format!("IO error: {err}"))
     }
 }
+
+impl From<reqwest::Error> for ApiError {
+    fn from(err: reqwest::Error) -> Self {
+        Self::internal(format!("HTTP client error: {err}"))
+    }
+}