chore: fix build dependencies and frontend config

Migrate Docker SDK from github.com/docker/docker (+incompatible)
to github.com/moby/moby/client v0.3.0 + moby/moby/api v1.54.0
(proper Go modules). Adapt all container/image/network operations
to the new moby API (Filters, ContainerListOptions, PullResponse,
InspectResult, etc.). Add AsyncTriggerDeploy runDeploy method.

Fix SvelteKit build: disable prerender, set strict=false for SPA,
bump vite-plugin-svelte to v5 for vite 6 compat.

Add .dockerignore to exclude .git, node_modules, plans.

internal/deployer/deployer.go

@@ -17,7 +17,7 @@ import (
 	"github.com/alexei/docker-watcher/internal/notify"
 	"github.com/alexei/docker-watcher/internal/npm"
 	"github.com/alexei/docker-watcher/internal/store"
-	"github.com/docker/docker/api/types/mount"
+	"github.com/moby/moby/api/types/mount"
 	"github.com/google/uuid"
 )
 
@@ -118,6 +118,79 @@ func (d *Deployer) AsyncTriggerDeploy(ctx context.Context, projectID, stageID, i
 	return deploy.ID, nil
 }
 
+// runDeploy is the internal deploy pipeline used by AsyncTriggerDeploy.
+// It assumes the deploy record already exists and project/stage are validated.
+func (d *Deployer) runDeploy(ctx context.Context, project store.Project, stage store.Stage, deployID string, imageTag string) error {
+	settings, err := d.store.GetSettings()
+	if err != nil {
+		if updateErr := d.store.UpdateDeployStatus(deployID, "failed", err.Error()); updateErr != nil {
+			slog.Warn("update deploy status", "error", updateErr)
+		}
+		return fmt.Errorf("get settings: %w", err)
+	}
+
+	slog.Info("starting deploy",
+		"deploy_id", deployID,
+		"project", project.Name,
+		"stage", stage.Name,
+		"tag", imageTag,
+	)
+	d.logDeploy(deployID, fmt.Sprintf("Starting deploy of %s:%s for project %s, stage %s", project.Image, imageTag, project.Name, stage.Name), "info")
+
+	// Enforce max_instances before deploying.
+	if err := d.enforceMaxInstances(ctx, stage, deployID, settings); err != nil {
+		d.logDeploy(deployID, fmt.Sprintf("Failed to enforce max instances: %v", err), "error")
+	}
+
+	var containerID string
+	var npmProxyID int
+	var instanceID string
+	var deployErr error
+
+	if stage.MaxInstances == 1 {
+		containerID, npmProxyID, instanceID, deployErr = d.blueGreenDeploy(ctx, project, stage, settings, deployID, imageTag)
+	} else {
+		containerID, npmProxyID, instanceID, deployErr = d.executeDeploy(ctx, project, stage, settings, deployID, imageTag)
+	}
+
+	if deployErr != nil {
+		d.logDeploy(deployID, fmt.Sprintf("Deploy failed: %v", deployErr), "error")
+		d.publishDeployStatus(deployID, project.ID, stage.ID, imageTag, "failed", deployErr.Error())
+		d.rollback(ctx, deployID, containerID, npmProxyID, instanceID)
+
+		d.notifier.Send(settings.NotificationURL, notify.Event{
+			Type:     "deploy_failure",
+			Project:  project.Name,
+			Stage:    stage.Name,
+			ImageTag: imageTag,
+			Error:    deployErr.Error(),
+		})
+
+		return fmt.Errorf("deploy failed: %w", deployErr)
+	}
+
+	if err := d.store.UpdateDeployStatus(deployID, "success", ""); err != nil {
+		slog.Warn("update deploy status to success", "error", err)
+	}
+	d.publishDeployStatus(deployID, project.ID, stage.ID, imageTag, "success", "")
+
+	subdomain := d.buildSubdomain(project, stage, settings, imageTag)
+	fullURL := fmt.Sprintf("https://%s.%s", subdomain, settings.Domain)
+
+	d.logDeploy(deployID, fmt.Sprintf("Deploy successful: %s", fullURL), "info")
+
+	d.notifier.Send(settings.NotificationURL, notify.Event{
+		Type:      "deploy_success",
+		Project:   project.Name,
+		Stage:     stage.Name,
+		ImageTag:  imageTag,
+		Subdomain: subdomain,
+		URL:       fullURL,
+	})
+
+	return nil
+}
+
 // TriggerDeploy is the synchronous entry point for deployments (used by poller and webhook).
 // It orchestrates the full flow: pull image -> create container -> start -> configure proxy -> health check.
 // On failure, it rolls back (removes container, deletes proxy host, updates status).