docs(catalog): mark bookstack as verified (2026-08-02)

- Add note pointing to where linuxserver image env var names
  can be discovered (/config/www/.env inside the running container)
- Mention the image's appkey command for generating APP_KEY

catalog.yaml

@@ -114,8 +114,13 @@ apps:
     db: mariadb
     architecture: app_db
     first_run: setup_wizard
-    test_status: untested
+    test_status: verified
+    test_date: 2026-08-02
     repo: https://gitea.damconsulting.llc/dam/ts-bookstack
+    notes: |
+      linuxserver image — see /config/www/.env in the running container
+      for the actual env var names this image expects. Generate APP_KEY
+      with the image's `appkey` command.
 
   - service: calibre-web
     display_name: Calibre-Web