Update to Traefik v3

The default docker swarm endpoint mode (vip) introduces unnecessary
indirection in the communication between services, namely the
docker-proxy and a dynamic haproxy endpoint container. This commit
switches the socket-proxy service to endpoint_mode: dnsrr by default and
the traefik service when using host-mode port publishing.

I would strongly recommend considering switching to host-mode port
publishing by default, especially as most coop-cloud deployments are
single-server.

See: toolshed/organising#648

Thanks to @mirsal. Rebased and merged from the following commit.
abbb3255f8

.env.sample

@@ -10,7 +10,7 @@ LETS_ENCRYPT_EMAIL=certs@example.com
 # DASHBOARD_ENABLED=true
 # WARN, INFO etc.
 LOG_LEVEL=WARN
-LOG_MAX_AGE=0
+LOG_MAX_AGE=1
 
 # This is here so later lines can extend it; you likely don't wanna edit
 COMPOSE_FILE="compose.yml"

compose.yml

@@ -3,7 +3,7 @@ version: "3.8"
 
 services:
   app:
-    image: "traefik:v2.11.14"
+    image: "traefik:v3.3.7"
     # Note(decentral1se): *please do not* add any additional ports here.
     # Doing so could break new installs with port conflicts. Please use
     # the usual `compose.$app.yml` approach for any additional ports
@@ -27,7 +27,7 @@ services:
     environment:
       - DASHBOARD_ENABLED
       - LOG_LEVEL
-      - LOG_MAX_AGE=${LOG_MAX_AGE:0}
+      - LOG_MAX_AGE
     healthcheck:
       test: ["CMD", "traefik", "healthcheck"]
       interval: 30s
@@ -48,12 +48,14 @@ services:
         - "traefik.http.routers.${STACK_NAME}.tls.certresolver=${LETS_ENCRYPT_ENV}"
         - "traefik.http.routers.${STACK_NAME}.service=api@internal"
         - "traefik.http.routers.${STACK_NAME}.middlewares=security@file"
-        - "coop-cloud.${STACK_NAME}.version=3.1.0+v2.11.14"
+        - "coop-cloud.${STACK_NAME}.version=3.1.0+v2.11.24"
         - "coop-cloud.${STACK_NAME}.timeout=${TIMEOUT:-120}"
         - "backupbot.backup=${ENABLE_BACKUPS:-true}"
 
   socket-proxy:
     image: lscr.io/linuxserver/socket-proxy:1.26.2-r0-ls30
+    deploy:
+      endpoint_mode: dnsrr
     environment:
       - ALLOW_START=0
       - ALLOW_STOP=0
@@ -77,7 +79,7 @@ services:
       - SECRETS=0
       - SERVICES=1 # Needs access
       - SESSION=0
-      - SWARM=0
+      - SWARM=1
       - SYSTEM=0
       - TASKS=1 # Needs access
       - VERSION=1 # Needs access

release/2.9.1+v2.11.14

@@ -0,0 +1 @@
+Reverts max log retention

release/3.0.0+v2.11.22

@@ -0,0 +1,2 @@
+socket-proxy: switch to endpoint-mode dnsrr instead of vip
+See https://git.coopcloud.tech/coop-cloud/traefik/pulls/50.

release/3.1.0+v2.11.14

@@ -1 +0,0 @@
-Adds log retention configuration option

traefik.yml.tmpl

@@ -1,15 +1,16 @@
 ---
+core:
+  defaultRuleSyntax: v2
+ 
 log:
   level: {{ env "LOG_LEVEL" }}
   maxAge: {{ env "LOG_MAX_AGE" }}
 
-
 providers:
-  docker:
+  swarm:
     endpoint: "tcp://socket-proxy:2375"
     exposedByDefault: false
     network: proxy
-    swarmMode: true
   {{ if eq (env "FILE_PROVIDER_DIRECTORY_ENABLED") "1" }}
   file:
     directory: /etc/traefik/file-providers