Fix CI build path by tracking cmd/rexd entrypoint.

Narrow the gitignore binary rule to the repo-root `/rexd` artifact so `cmd/rexd/main.go` is included in source control and Actions can build `./cmd/rexd`.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: samiralibabic

.gitignore

@@ -1,4 +1,4 @@
-rexd
+/rexd
 rexd_verify.txt
 .DS_Store
 

cmd/rexd/main.go

@@ -0,0 +1,56 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"log"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/samiralibabic/rexd/internal/config"
+	"github.com/samiralibabic/rexd/internal/server"
+)
+
+func main() {
+	var cfgPath string
+	var stdio bool
+	var httpListen string
+	flag.StringVar(&cfgPath, "config", "/etc/rexd/config.toml", "path to rexd config")
+	flag.BoolVar(&stdio, "stdio", false, "run JSON-RPC on stdio")
+	flag.StringVar(&httpListen, "http", "", "listen address for HTTP/WS transport")
+	flag.Parse()
+
+	cfg, err := config.Load(cfgPath)
+	if err != nil {
+		log.Fatalf("load config: %v", err)
+	}
+	if stdio {
+		cfg.Server.Stdio = true
+	}
+	if httpListen != "" {
+		cfg.Server.HTTPListen = httpListen
+	}
+
+	svc, err := server.NewService(cfg)
+	if err != nil {
+		log.Fatalf("create service: %v", err)
+	}
+
+	ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
+	defer cancel()
+
+	if cfg.Server.Stdio {
+		if err := server.RunStdio(ctx, svc, os.Stdin, os.Stdout); err != nil {
+			log.Fatalf("stdio server failed: %v", err)
+		}
+		return
+	}
+
+	if cfg.Server.HTTPListen == "" {
+		log.Fatal("either --stdio or --http must be configured")
+	}
+	if err := server.RunHTTP(ctx, cfg, svc); err != nil {
+		log.Fatalf("http server failed: %v", err)
+	}
+}