fix(plane): set proxy SITE_ADDRESS and TRUSTED_PROXIES to fix Caddyfile crash

The plane-proxy Caddyfile.ce ends with a `{$SITE_ADDRESS} { import plane_proxy }`
block. SITE_ADDRESS has no inline default upstream, so when it is unset the block
becomes keyless and Caddy aborts with:

  adapting config using caddyfile: server block without any key is global
  configuration, and if used, it must be first

Expose SITE_ADDRESS (:80, matching the proxy `expose: ["80"]` + domain port 80,
since Dokploy terminates TLS upstream) and TRUSTED_PROXIES (0.0.0.0/0, matching
the Caddyfile inline default) on the proxy env, and document both in template.toml
so they render into the generated env. Reported and verified by @RDeluxe in #912.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

blueprints/plane/docker-compose.yml

@@ -37,6 +37,10 @@ x-proxy-env: &proxy-env
   APP_DOMAIN: ${APP_DOMAIN:-localhost}
   FILE_SIZE_LIMIT: ${FILE_SIZE_LIMIT:-5242880}
   BUCKET_NAME: ${AWS_S3_BUCKET_NAME:-uploads}
+  # Caddy proxy: listen address (no upstream default in Caddyfile -> must be set,
+  # else the `{$SITE_ADDRESS} { ... }` block is keyless and Caddy aborts) + trusted proxies
+  SITE_ADDRESS: ${SITE_ADDRESS:-:80}
+  TRUSTED_PROXIES: ${TRUSTED_PROXIES:-0.0.0.0/0}
 
 x-mq-env: &mq-env
   RABBITMQ_HOST: ${RABBITMQ_HOST:-plane-mq}

blueprints/plane/template.toml

@@ -45,6 +45,10 @@ env = [
   "AWS_S3_ENDPOINT_URL=http://plane-minio:9000",
   "AWS_S3_BUCKET_NAME=uploads",
   "FILE_SIZE_LIMIT=5242880",
+  # Caddy proxy listen address + trusted proxies (required by the plane-proxy Caddyfile;
+  # SITE_ADDRESS has no upstream default, so leaving it unset crashes the proxy)
+  "SITE_ADDRESS=:80",
+  "TRUSTED_PROXIES=0.0.0.0/0",
   "MINIO_ENDPOINT_SSL=0",
   "DEBUG=0",
   "GUNICORN_WORKERS=1",