wger: 2.6 with the full DJANGO_DB_* set (2.3 no longer exists upstream)

Correcting my own earlier revert. Reverting to 2.3 was WRONG: wger/server:2.3 is
no longer published on Docker Hub (only 2.4, 2.5, 2.6 resolve), so that pin could
not be pulled at all -- the deploy was accepted and no container was ever created.
An unpullable pin is strictly worse than the problem it was meant to avoid.

Every available version (2.4/2.5/2.6, verified) reads the whole DJANGO_DB_* set
unconditionally, even with the sqlite engine. So supplying it is not a hack
around one version -- it is now the only way to run wger at all. Verified live:
2.6 with the full set boots and applies its migrations ('Applying auth.0001_initial
... OK').

USER/PASSWORD/HOST/PORT are ignored by the sqlite backend but must be present.
DJANGO_DB_DATABASE points into the existing wger_data volume (/home/wger/db),
which is where wger's own default sqlite file lived -- so an existing install is
not pointed at an empty database somewhere else.

Campaign 7 catalog sweep.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Nn3VgQk9iwEGgyx6QJ2NvE

templates/wger/docker-compose.yml

@@ -9,13 +9,25 @@
 
 services:
   wger:
-    image: wger/server:2.3
+    image: wger/server:2.6
     container_name: wger
     restart: unless-stopped
     environment:
       - TZ=Europe/Budapest
       - SECRET_KEY=${SECRET_KEY}
+      # A wger 2.4+ a TELJES DJANGO_DB_* halmazt beolvassa, akkor is, ha az
+      # engine sqlite -- enélkül indulás nélkül kilép ("Set the DJANGO_DB_USER
+      # environment variable"). Az USER/PASSWORD/HOST/PORT értékeket az sqlite
+      # backend figyelmen kívül hagyja, de jelen kell lenniük.
+      # A DATABASE a wger_data kötetre mutat (/home/wger/db), oda, ahol a wger
+      # saját alapértelmezett sqlite fájlja is volt -- így meglévő telepítés
+      # adatai nem "tűnnek el" egy másik útvonalra.
       - DJANGO_DB_ENGINE=django.db.backends.sqlite3
+      - DJANGO_DB_DATABASE=/home/wger/db/database.sqlite
+      - DJANGO_DB_USER=wger
+      - DJANGO_DB_PASSWORD=wger
+      - DJANGO_DB_HOST=localhost
+      - DJANGO_DB_PORT=5432
       - SITE_URL=https://${SUBDOMAIN}.${DOMAIN}
     volumes:
       - wger_data:/home/wger/db