docs: document app-only compose + fix dev.sh for relay profile

dev.sh still has to opt into the relay profile now that it's no
longer in the default set; otherwise `./dev.sh` would print "relay:
http://localhost:8081" but skip starting the container. README gets
a short compose section in Quick Start explaining the app-only
default and how to add --profile relay for a local relay.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

README.md

@@ -23,6 +23,22 @@ Open `http://localhost:8080` and set your password on first visit.
 
 The `-v hyprcrd-data:/var/www/html/data` flag persists the database across container restarts.
 
+### Via docker compose
+
+If you prefer compose, the bundled `docker-compose.yml` starts the app alone by default:
+
+```bash
+docker compose up -d     # just the app on :8088
+```
+
+To also bring up a local relay (for multi-tenant messaging / collab / chat), opt in via the `relay` profile:
+
+```bash
+docker compose --profile relay up -d    # app on :8088 + relay on :8081
+```
+
+Most installs talk to a remote relay, so the app-only default keeps the local setup minimal.
+
 ## Manual Installation
 
 ### 1. Clone
@@ -418,6 +434,8 @@ access via `.htaccess`).
 
 Starts hyprcrd on `http://localhost:8088` and the relay on `http://localhost:8081` in the same Docker network. Source files are bind-mounted — changes are live without rebuilding. From inside the hyprcrd container, the relay is reachable at `http://relay:80`.
 
+Under the hood this runs `docker compose --profile relay up --build`. The relay service lives behind the `relay` compose profile, so a plain `docker compose up` brings up only the app — handy when you're developing against a remote relay.
+
 ### Setup workflow
 
 1. Open the relay URL **from a desktop browser** — the setup wizard

dev.sh

@@ -1,9 +1,11 @@
 #!/bin/bash
-# Start hyprcrd + relay for local development
+# Start hyprcrd + relay for local development. The relay service is
+# behind a compose profile since it's opt-in — this script explicitly
+# opts in so you get both containers.
 
 cd "$(dirname "$0")"
 
-docker compose up -d --build
+docker compose --profile relay up -d --build
 
 echo ""
 echo "  hyprcrd:  http://localhost:8088"
@@ -11,3 +13,5 @@ echo "  relay:    http://localhost:8081"
 echo ""
 echo "  relay from hyprcrd container: http://relay:80"
 echo ""
+echo "  (for app-only, drop the relay profile:  docker compose up -d)"
+echo ""