Add CWA_ENABLED to run Bindery without CWA

With CWA_ENABLED=false, Bindery ignores the CWA settings, makes no request
to CWA, and shows nothing about CWA in the log and the web interface. A
set INGEST_DIR still gets each changed book as a plain epub.

Without it, the log names each CWA function that a missing setting turns
off.

README.md

@@ -53,6 +53,7 @@ Environment variables set the configuration. **Restart the container after a cha
 
 | Variable | Description | Default value |
 | --- | --- | --- |
+| `CWA_ENABLED` | `false` if you have no CWA. See "Without CWA". | `true` |
 | `CWA_URL` | The address of CWA, for example `http://calibre-web-automated:8083` | None |
 | `CWA_USERNAME`, `CWA_PASSWORD` | The CWA account of Bindery. Leave them unset if CWA asks for no login. | None |
 | `CWA_DB_PATH` | Calibre-Web's `app.db`, for logins. See "CWA logins". | None |
@@ -72,7 +73,7 @@ Environment variables set the configuration. **Restart the container after a cha
 | `SESSION_COOKIE_SECURE` | `true` if users reach Bindery only over HTTPS | `false` |
 | `TRUST_PROXY` | `true` if a reverse proxy sends the client address. See "Lockouts and sessions". | `false` |
 | `URL_BASE` | A path prefix, such as `/bindery`. See "Reverse proxy". | None |
-| `INGEST_DIR` | The CWA ingest folder. If unset, all uploads stay paused. Bindery does not make this folder. | None |
+| `INGEST_DIR` | The CWA ingest folder. If unset, all uploads stay paused. Bindery does not make this folder. Without CWA, a folder for the built ePubs. | None |
 | `CONFIG_DIR` | The story database and `personal.ini` | `/config` |
 | `TMP_DIR` | The folder for the built ePubs. Bindery keeps the last build of each story. | `/tmp/bindery` |
 | `LOG_LEVEL` | The log level | `INFO` |
@@ -81,11 +82,26 @@ Separate the values in a list with commas.
 
 ### Without CWA
 
-Leave `INGEST_DIR`, `CWA_URL` and `CALIBRE_DB_PATH` unset to run Bindery without CWA.
-Bindery still downloads chapters and builds ePubs. Download the books from each story page.
+Set `CWA_ENABLED=false` to run Bindery without CWA. Bindery still downloads chapters and builds
+ePubs. Download the books from each story page.
 
-If you use the example Compose file, remove its CWA connection values, `INGEST_DIR` and the ingest volume mount.
-Use `AUTH_METHOD=local` or `proxy` for logins. On a private network, you can use `AUTH_METHOD=none`.
+With `CWA_ENABLED=false`:
+
+- Bindery makes no request to CWA. It ignores `CWA_URL`, `CWA_USERNAME`, `CWA_PASSWORD`,
+  `CWA_DB_PATH` and `CALIBRE_DB_PATH`.
+- The web interface and the log show nothing about CWA. The pause, the library links and the
+  approvals do not apply.
+- If `INGEST_DIR` is set, Bindery puts each changed book in that folder as a plain ePub. Use this to
+  import the books into other software. Each file gets a new name, so Bindery never replaces a file
+  in the folder.
+- `AUTH_METHOD=cwa` does not work. Use `local` or `proxy`. On a private network, you can use `none`.
+
+If you use the example Compose file, remove its CWA connection values. Keep `INGEST_DIR` and its
+volume mount only if you want the ePubs in a folder.
+
+Without `CWA_ENABLED=false`, Bindery expects CWA. At each start, the log then has a warning for each
+function that a missing `INGEST_DIR`, `CWA_URL` or `CALIBRE_DB_PATH` turns off. Bindery still
+downloads chapters and builds ePubs.
 
 Without `INGEST_DIR`, Settings shows "Pause all uploads" checked and a highlighted explanation.
 You cannot clear that checkbox until you set `INGEST_DIR` and restart Bindery.
@@ -590,7 +606,7 @@ enough to work on downloads, chapters, rules and the web interface.
 
 ```bash
 mkdir -p dev/ingest
-CONFIG_DIR=dev/config INGEST_DIR=dev/ingest TMP_DIR=dev/tmp uv run python -m bindery
+CWA_ENABLED=false CONFIG_DIR=dev/config INGEST_DIR=dev/ingest TMP_DIR=dev/tmp uv run python -m bindery
 ```
 
 Open `http://127.0.0.1:8085`. The folders go in `dev/`, which git ignores. To look at an ePub, use