feature: Add /api/info for simple instance stats

src/main/java/eu/m724/mstats/api/resource/InfoApiResource.java

@@ -0,0 +1,49 @@
+package eu.m724.mstats.api.resource;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import eu.m724.mstats.orm.Plugin;
+import eu.m724.mstats.orm.Server;
+import jakarta.ws.rs.GET;
+import jakarta.ws.rs.Path;
+import jakarta.ws.rs.Produces;
+import jakarta.ws.rs.core.MediaType;
+import jakarta.ws.rs.core.Response;
+import org.eclipse.microprofile.config.inject.ConfigProperty;
+
+@Path("/api/info")
+@Produces(MediaType.APPLICATION_JSON)
+public class InfoApiResource {
+    @ConfigProperty(name = "quarkus.application.name")
+    String applicationName;
+
+    @ConfigProperty(name = "quarkus.application.version")
+    String applicationVersion;
+
+    @Path("/")
+    @GET
+    public Response info() {
+        InfoResponse response = new InfoResponse();
+        response.applicationInfo = new ApplicationInfo(applicationName, applicationVersion);
+        response.servers = Server.count();
+        response.plugins = Plugin.count();
+
+        // TODO Add more data like server versions
+
+        return Response.ok(response).build();
+    }
+
+    public static class InfoResponse {
+        public InfoResponse() {}
+
+        @JsonProperty("application")
+        public ApplicationInfo applicationInfo;
+
+        @JsonProperty("servers")
+        public long servers;
+
+        @JsonProperty("plugins")
+        public long plugins;
+    }
+
+    public record ApplicationInfo(String name, String version) { }
+}