CI: publish the builds as a download site, deploy via Coolify

The deployed image is now a small nginx site instead of a bare app
tree: the Linux app (with its runtime), a universal jar, the Android
APK, SHA256SUMS and a landing page showing the commit and build date.

- desktop: universalJar bundles the Skiko natives for Linux, macOS and
  Windows (Compose's own jar only carries the building OS's).
- Dockerfile: the build stage runs tests and builds every artifact;
  site/assemble.sh lays them out; the final stage is nginx:alpine.
- .ci: after the image is built, `main` calls the beta Coolify hook and
  `release` the production one; other branches only build.
- .dockerignore keeps local.properties and secrets out of the build.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/site/nginx.conf b/site/nginx.conf
new file mode 100644
index 0000000..310d68d
--- /dev/null
+++ b/site/nginx.conf
@@ -0,0 +1,20 @@
+server {
+    listen 80;
+    root /usr/share/nginx/html;
+    index index.html;
+
+    # a new build replaces these files in place, so have clients check
+    add_header Cache-Control "no-cache";
+
+    location ~ \.apk$ {
+        default_type application/vnd.android.package-archive;
+        add_header Cache-Control "no-cache";
+    }
+    location = /SHA256SUMS {
+        default_type text/plain;
+        add_header Cache-Control "no-cache";
+    }
+    location / {
+        try_files $uri $uri/ =404;
+    }
+}