feat(conga,dev): worker and scheduler reports, summer dev runs serve

- queue:work and schedule:run print a startup summary and a shutdown
  report on a terminal, log them as records otherwise, and return nil
  after a clean stop
- schedule:run --once ends with 'Ran N due entries (M failed)'
- summer dev runs bin/<app> serve with the forwarded global options,
  reports through Output, stops the old server before starting the new
  one and prints a dev report on Ctrl+C (exit 0)
- lagoon.DatabaseLabel describes a DSN without its secrets
- Long help and examples for queue:work, schedule:run, dev, docs:serve

cmd/summer/docs.go

@@ -89,6 +89,14 @@ func docsServeCommand() bonfire.Command {
 	return bonfire.Command{
 		Name:        "docs:serve",
 		Description: "Build the documentation site and preview it on a local address",
+		Long: `Builds the documentation site like docs:build into a temporary directory and
+serves it on a loopback address. It watches the docs sources and the files
+their src= references point to, and rebuilds on change; a failed rebuild keeps
+the last good site. Ctrl+C stops the server and exits 0.`,
+		Examples: []bonfire.Example{
+			{Command: "docs:serve", Description: "Preview the docs of the current repository on " + docsite.DefaultServeAddr},
+			{Command: "docs:serve --addr 127.0.0.1:4100", Description: "Use another port"},
+		},
 		Flags: []bonfire.Flag{
 			{Name: "root", Description: "Repository root; src= paths and modules/ resolve against it", Default: "."},
 			{Name: "src", Description: "Docs source directory (default <root>/docs)"},