feat: add CPU and memory resource limits per app

- Add cpu_limit (REAL) and memory_limit (INTEGER) columns to apps table
  via migration 007
- Add CPULimit and MemoryLimit fields to App model with full CRUD support
- Add resource limits fields to app edit form with human-friendly
  memory input (e.g. 256m, 1g, 512k)
- Pass CPU and memory limits to Docker container creation via
  NanoCPUs and Memory host config fields
- Extract Docker container creation helpers (buildEnvSlice, buildMounts,
  buildResources) for cleaner code
- Add formatMemoryBytes template function for display
- Add comprehensive tests for parsing, formatting, model persistence,
  and container options

internal/service/deploy/deploy_container_test.go

@@ -2,6 +2,7 @@ package deploy_test
 
 import (
 	"context"
+	"database/sql"
 	"log/slog"
 	"os"
 	"testing"
@@ -43,3 +44,93 @@ func TestBuildContainerOptionsUsesImageID(t *testing.T) {
 		t.Errorf("expected Name=%q, got %q", "upaas-myapp", opts.Name)
 	}
 }
+
+func TestBuildContainerOptionsNoResourceLimits(t *testing.T) {
+	t.Parallel()
+
+	db := database.NewTestDatabase(t)
+
+	app := models.NewApp(db)
+	app.Name = "nolimits"
+
+	err := app.Save(context.Background())
+	if err != nil {
+		t.Fatalf("failed to save app: %v", err)
+	}
+
+	log := slog.New(slog.NewTextHandler(os.Stderr, nil))
+	svc := deploy.NewTestService(log)
+
+	opts, err := svc.BuildContainerOptionsExported(
+		context.Background(), app, docker.ImageID("test:latest"),
+	)
+	if err != nil {
+		t.Fatalf("buildContainerOptions returned error: %v", err)
+	}
+
+	if opts.CPULimit != 0 {
+		t.Errorf("expected CPULimit=0, got %v", opts.CPULimit)
+	}
+
+	if opts.MemoryLimit != 0 {
+		t.Errorf("expected MemoryLimit=0, got %v", opts.MemoryLimit)
+	}
+}
+
+func TestBuildContainerOptionsCPULimit(t *testing.T) {
+	t.Parallel()
+
+	db := database.NewTestDatabase(t)
+
+	app := models.NewApp(db)
+	app.Name = "cpulimit"
+	app.CPULimit = sql.NullFloat64{Float64: 0.5, Valid: true}
+
+	err := app.Save(context.Background())
+	if err != nil {
+		t.Fatalf("failed to save app: %v", err)
+	}
+
+	log := slog.New(slog.NewTextHandler(os.Stderr, nil))
+	svc := deploy.NewTestService(log)
+
+	opts, err := svc.BuildContainerOptionsExported(
+		context.Background(), app, docker.ImageID("test:latest"),
+	)
+	if err != nil {
+		t.Fatalf("buildContainerOptions returned error: %v", err)
+	}
+
+	if opts.CPULimit != 0.5 {
+		t.Errorf("expected CPULimit=0.5, got %v", opts.CPULimit)
+	}
+}
+
+func TestBuildContainerOptionsMemoryLimit(t *testing.T) {
+	t.Parallel()
+
+	db := database.NewTestDatabase(t)
+
+	app := models.NewApp(db)
+	app.Name = "memlimit"
+	app.MemoryLimit = sql.NullInt64{Int64: 536870912, Valid: true} // 512m
+
+	err := app.Save(context.Background())
+	if err != nil {
+		t.Fatalf("failed to save app: %v", err)
+	}
+
+	log := slog.New(slog.NewTextHandler(os.Stderr, nil))
+	svc := deploy.NewTestService(log)
+
+	opts, err := svc.BuildContainerOptionsExported(
+		context.Background(), app, docker.ImageID("test:latest"),
+	)
+	if err != nil {
+		t.Fatalf("buildContainerOptions returned error: %v", err)
+	}
+
+	if opts.MemoryLimit != 536870912 {
+		t.Errorf("expected MemoryLimit=536870912, got %v", opts.MemoryLimit)
+	}
+}