rebrand: MangaBM → BookmarkManager, add novel library support (#15)

Two intertwined changes — the rebrand and the novel library were developed on
the same branch because the novel UI plumbing is part of the new "Bookmark
Manager" wordmark in the web shell.

## What it does

- **Rebrand**: MangaBM → BookmarkManager across the Go module, compose stack,
  env vars, Traefik hostnames, container/image names, userscript storage
  prefixes (`mangabm:cache` → `bmgr:manga:cache`, `mangabm:queue` → `bmgr:manga:queue`),
  and docs.
- **Novel library**: same backend, two libraries. New `kind` column splits
  bookmarks into `manga` / `novel`; PUT validates it. Two userscripts:
  - `manga-bookmark.user.js` — unchanged behaviour, just stamps its own `kind`.
  - `novel-bookmark.user.js` — separate Violentmonkey install with adapters
    for **novelfull.com** (polled via headless browser — Cloudflare JS
    challenge) and **lightnovelworld.net** (polled via plain TLS).
- **Web UI**: library switch on the app shell. Login art, libswitch, and
  novel-site colours from the Cinder design snapshot.

## Plumbing

- `addedColumns` ALTER for `kind` runs on first start after upgrade; every
  pre-existing row is backfilled to `'manga'`. No manual SQL, no down-time.
- `ALLOWED_ORIGINS` gains the two novel sites.
- New `NOVEL_USERSCRIPT_PATH` env (default `/userscript/novel-bookmark.user.js`),
  bindmounted alongside the manga script.
- Traefik router names `mangabm*` → `bmapi*` / `bmweb*`.

## Test status

- `go test ./...` — green
- `node --test userscript/test/logic.test.js` — 34 pass
- `node --test userscript/test/novel-logic.test.js` — 11 pass
- `node --check` on both userscripts — clean

## Notes for the redeploy

.env keys were renamed (`MANGA_API_HOST` → `BOOKMARK_API_HOST`,
`MANGA_WEB_HOST` → `BOOKMARK_WEB_HOST`). Update DNS / Traefik labels on the
prod override before pulling, otherwise the public hostnames go dark.
See the redeploy instructions I'll post next to this PR.

Reviewed-on: #15
Co-authored-by: Sulthan Zaki <sultankiki05@gmail.com>
Co-committed-by: Sulthan Zaki <sultankiki05@gmail.com>

backend/internal/latest/sites_test.go

@@ -52,6 +52,33 @@ const kaganeAPIFixture = `
 {"book_id":"c","title":"Episode 40.5","chapter_no":"40.5","sort_no":40}]}
 `
 
+// Trimmed from https://novelfull.com/reverend-insanity.html fetched 2026-08-05.
+// The page carries a newest-first "latest chapters" widget above an
+// oldest-first paginated list, so the newest anchor is deliberately NOT last —
+// only a maximum finds it. The final anchor belongs to another series and must
+// be excluded by slug scoping.
+const novelfullSeriesFixture = `
+<div class="l-chapters">
+  <a href="/reverend-insanity/chapter-2334-fang-yuan-and-giant-sun.html">Chapter 2334</a>
+  <a href="/reverend-insanity/chapter-2333-three-venerables.html">Chapter 2333</a>
+</div>
+<ul class="list-chapter">
+  <li><a href="/reverend-insanity/chapter-1.html">Chapter 1</a></li>
+  <li><a href="/reverend-insanity/chapter-2.html">Chapter 2</a></li>
+</ul>
+<a href="/release-that-witch/chapter-9999.html">Chapter 9999</a>
+`
+
+// Trimmed from https://lightnovelworld.net/novel/a-will-eternal/ fetched
+// 2026-08-05. Its chapter anchors are absolute and flat — /<slug>-chapter-<n>/
+// at the site root, not under /novel/. The last anchor is another series'.
+const lnwSeriesFixture = `
+<a href="https://lightnovelworld.net/a-will-eternal-chapter-1/">Chapter 1</a>
+<a href="https://lightnovelworld.net/a-will-eternal-chapter-1317/">Chapter 1317</a>
+<a href="https://lightnovelworld.net/a-will-eternal-chapter-1298/">Chapter 1298</a>
+<a href="https://lightnovelworld.net/overgeared-chapter-9999/">Chapter 9999</a>
+`
+
 func TestLatestChapterFrom(t *testing.T) {
 	const asuraURL = "https://asurascans.com/comics/chronicles-of-the-demon-faction-f886a8af"
 	const demonicURL = "https://demonicscans.org/manga/Catastrophic-Necromancer"
@@ -146,6 +173,48 @@ func TestLatestChapterFrom(t *testing.T) {
 			body:      challengeFixture,
 			wantOK:    false,
 		},
+		{
+			name:      "novelfull takes the max and ignores another series",
+			site:      "novelfull",
+			seriesURL: "https://novelfull.com/reverend-insanity.html",
+			body:      novelfullSeriesFixture,
+			wantOK:    true, wantNum: 2334, wantLabel: "Chapter 2334",
+		},
+		{
+			name:      "novelfull yields nothing on a challenge page",
+			site:      "novelfull",
+			seriesURL: "https://novelfull.com/reverend-insanity.html",
+			body:      challengeFixture,
+			wantOK:    false,
+		},
+		{
+			name:      "novelfull with an unparseable series url",
+			site:      "novelfull",
+			seriesURL: "https://novelfull.com/genre/Fantasy",
+			body:      novelfullSeriesFixture,
+			wantOK:    false,
+		},
+		{
+			name:      "lightnovelworld takes the max and ignores another series",
+			site:      "lightnovelworld",
+			seriesURL: "https://lightnovelworld.net/novel/a-will-eternal/",
+			body:      lnwSeriesFixture,
+			wantOK:    true, wantNum: 1317, wantLabel: "Chapter 1317",
+		},
+		{
+			name:      "lightnovelworld tolerates a series url with no trailing slash",
+			site:      "lightnovelworld",
+			seriesURL: "https://lightnovelworld.net/novel/a-will-eternal",
+			body:      lnwSeriesFixture,
+			wantOK:    true, wantNum: 1317, wantLabel: "Chapter 1317",
+		},
+		{
+			name:      "lightnovelworld yields nothing on a challenge page",
+			site:      "lightnovelworld",
+			seriesURL: "https://lightnovelworld.net/novel/a-will-eternal/",
+			body:      challengeFixture,
+			wantOK:    false,
+		},
 	}
 
 	for _, tt := range tests {