feat: funciones infra — Docker, deploy, build y health check

Funciones impuras para gestión de contenedores: docker_build_image,
docker_compose_up/down, docker_volume_create/list/remove,
generate_dockerfile, write_dockerfile, go_build_binary, health_check_http,
deploy_app y stop_app. Todas con tests unitarios donde aplica.

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

functions/infra/generate_dockerfile_test.go

@@ -0,0 +1,67 @@
+package infra
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestGenerateDockerfile(t *testing.T) {
+	t.Run("contiene stage builder con golang:1.23-alpine", func(t *testing.T) {
+		got := GenerateDockerfile("myapp", 8080, nil)
+		if !strings.Contains(got, "FROM golang:1.23-alpine AS builder") {
+			t.Errorf("expected FROM golang:1.23-alpine AS builder, got:\n%s", got)
+		}
+	})
+
+	t.Run("contiene stage final con alpine:latest", func(t *testing.T) {
+		got := GenerateDockerfile("myapp", 8080, nil)
+		if !strings.Contains(got, "FROM alpine:latest") {
+			t.Errorf("expected FROM alpine:latest, got:\n%s", got)
+		}
+	})
+
+	t.Run("incluye EXPOSE cuando port mayor a cero", func(t *testing.T) {
+		got := GenerateDockerfile("myapp", 8080, nil)
+		if !strings.Contains(got, "EXPOSE 8080") {
+			t.Errorf("expected EXPOSE 8080, got:\n%s", got)
+		}
+	})
+
+	t.Run("no incluye EXPOSE cuando port es cero", func(t *testing.T) {
+		got := GenerateDockerfile("myapp", 0, nil)
+		if strings.Contains(got, "EXPOSE") {
+			t.Errorf("expected no EXPOSE directive, got:\n%s", got)
+		}
+	})
+
+	t.Run("env vars aparecen ordenadas alfabeticamente", func(t *testing.T) {
+		got := GenerateDockerfile("myapp", 8080, map[string]string{
+			"Z_VAR": "z",
+			"A_VAR": "a",
+			"M_VAR": "m",
+		})
+		posA := strings.Index(got, "ENV A_VAR=a")
+		posM := strings.Index(got, "ENV M_VAR=m")
+		posZ := strings.Index(got, "ENV Z_VAR=z")
+		if posA < 0 || posM < 0 || posZ < 0 {
+			t.Fatalf("ENV vars no encontradas en:\n%s", got)
+		}
+		if !(posA < posM && posM < posZ) {
+			t.Errorf("ENV vars no ordenadas: A=%d M=%d Z=%d", posA, posM, posZ)
+		}
+	})
+
+	t.Run("binaryName aparece en ENTRYPOINT", func(t *testing.T) {
+		got := GenerateDockerfile("mycli", 9090, nil)
+		if !strings.Contains(got, `ENTRYPOINT ["./mycli"]`) {
+			t.Errorf("expected ENTRYPOINT with mycli, got:\n%s", got)
+		}
+	})
+
+	t.Run("env vars vacias no generan instrucciones ENV", func(t *testing.T) {
+		got := GenerateDockerfile("myapp", 8080, map[string]string{})
+		if strings.Contains(got, "ENV ") {
+			t.Errorf("expected no ENV directives for empty map, got:\n%s", got)
+		}
+	})
+}