feat(reader): continue a comic series from the last page

Finishing an issue offered no way onward, so the next one had to be opened from the library.
Resolve the next readable book server-side with one keyset query, offer it on the last page, and
let an opt-in setting cross over on a further page turn. The reader route now remounts on a param
change, without which it would keep rendering the book it was mounted with.

Also cast the compared value in compareSeriesIndexSql: as a bare parameter Postgres could not type
it inside the null test and rejected the statement.

Closes #998

packages/types/src/reader-settings.ts

@@ -54,6 +54,13 @@ export function getFormatGroup(format: string): ReaderFormatGroup {
   return FORMAT_TO_GROUP[format.toLowerCase()] ?? "epub";
 }
 
+/** Formats a given reader can open, so a caller can ask for "another file this same reader handles". */
+export function getOpenableFormatsForGroup(group: ReaderFormatGroup): string[] {
+  return Object.entries(FORMAT_TO_GROUP)
+    .filter(([format, formatGroup]) => formatGroup === group && READER_OPENABLE_FORMATS.has(format))
+    .map(([format]) => format);
+}
+
 export interface EpubReaderSettings {
   themeName: string; // matches one of the reader's built-in theme names
   isDark: boolean;
@@ -98,6 +105,8 @@ export interface CbxReaderSettings {
   forceTwoPage: boolean;
   widePageSingletonMode: "auto" | "disable";
   bgColor: "black" | "gray" | "white";
+  // Turning past the last page opens the next book in the series instead of stopping.
+  autoAdvance: boolean;
 }
 
 export interface AudioReaderSettings {
@@ -154,6 +163,7 @@ export const CBX_READER_DEFAULTS: CbxReaderSettings = {
   forceTwoPage: false,
   widePageSingletonMode: "auto",
   bgColor: "black",
+  autoAdvance: false,
 };
 
 export const AUDIO_READER_DEFAULTS: AudioReaderSettings = {

packages/types/src/series.ts

@@ -1,4 +1,5 @@
 import type { BooksPage } from "./book";
+import type { SeriesIndex } from "./series-index";
 
 export type SeriesSummary = {
   id: number;
@@ -31,3 +32,16 @@ export type SeriesDetail = {
 export type SeriesBooksPage = BooksPage & {
   seriesInfo: SeriesDetail;
 };
+
+/** A series book the reader can open next, already resolved down to the file it should open. */
+export type SeriesNextBook = {
+  bookId: number;
+  fileId: number;
+  format: string;
+  title: string | null;
+  seriesIndex: SeriesIndex | null;
+};
+
+export type SeriesNextBookResponse = {
+  next: SeriesNextBook | null;
+};