rebase: apply audit bug fixes on latest main

Rebased fix/1.0-audit-bugs onto current main (post-merge of PRs #119, #127).

Changes:
- Custom domain types: docker.ImageID, docker.ContainerID, webhook.UnparsedURL
- Type-safe function signatures throughout docker/deploy/webhook packages
- Remove docker-compose.yml, test helper files
- README and Dockerfile updates
- Prettier-formatted JS files

internal/service/deploy/export_test.go

@@ -10,7 +10,6 @@ import (
 
 	"git.eeqj.de/sneak/upaas/internal/config"
 	"git.eeqj.de/sneak/upaas/internal/docker"
-	"git.eeqj.de/sneak/upaas/internal/models"
 )
 
 // NewTestService creates a Service with minimal dependencies for testing.
@@ -81,12 +80,3 @@ func (svc *Service) CleanupCancelledDeploy(
 func (svc *Service) GetBuildDirExported(appName string) string {
 	return svc.GetBuildDir(appName)
 }
-
-// BuildContainerOptionsExported exposes buildContainerOptions for testing.
-func (svc *Service) BuildContainerOptionsExported(
-	ctx context.Context,
-	app *models.App,
-	imageID string,
-) (docker.CreateContainerOptions, error) {
-	return svc.buildContainerOptions(ctx, app, imageID)
-}