books: immersive reader route, PDF resume fix, scalable placeholder covers, read-only books mount in prod deploy, README

README.md

@@ -236,6 +236,30 @@ local database and migrations, and `db/reorg/README.md` for the one-time move of
 old flat schema to this layout. Catalog seeds (`npm run db:seed`, `db:seed:cod`, …)
 upsert reference data and run on every production deploy.
 
+## Book tracker
+
+`/trackers/books` is the public catalogue (covers, status, progress, stats). `/trackers/books/<id>`
+shows a book; the owner also sees files, notes, highlights and reading sessions there and can
+edit status, rating and progress. `/trackers/books/<id>/read` is the owner-only reader:
+EPUB, MOBI/AZW3 and FB2 open in [foliate-js](https://github.com/johnfactotum/foliate-js)
+(vendored in `static/vendor/foliate-js`, no conversion), PDFs in pdf.js. The reader remembers the
+position per file, autosaves progress and sessions, and stores highlights with notes.
+
+Files are never public. They are streamed (with Range support) by
+`/trackers/books/files/<id>` to the owner only; everyone else gets a 404. The reader, progress
+and notes endpoints are owner-only too (`src/lib/server/owner.ts`, backstopped in
+`hooks.server.ts`).
+
+Files are read from `BOOKS_ROOT` (default `/books` when it exists, otherwise `~/books`):
+
+- `BOOKS_ROOT/library/<books.files.path>` for book files (written by `scripts/books-ingest.py`)
+- `BOOKS_ROOT/covers/<books.works.cover_path>` for downloaded covers
+
+In production, `scripts/deploy-remote.sh` writes `/opt/personal-website/compose.books.yml`, which
+bind-mounts the host's `BOOKS_HOST_DIR` (default `/home/stan/books`) read-only at `/books` and sets
+`BOOKS_ROOT=/books`. Without a `library` directory there the deploy still succeeds, but files can't
+be opened.
+
 ## Money tracker
 
 `/projects/money-tracker` is restricted to administrator accounts. Its tables