feat(14.3-01): add summer new with a starter route and relative go.work

- build.NewApp writes sm-<name>-app: go.mod with a relative framework
  replace, go.work, summer.yaml, config/ and a starter plugin
- make:plugin gains an opt-in starter route (GET /{$}) in the same
  routes.go template; plain make:plugin output is unchanged
- plugin:add writes go.work use paths relative to the go.work directory
- bonfire accepts new as a bare tool command name

modules/bonfire/command_test.go

@@ -6,7 +6,7 @@ import (
 )
 
 func TestValidBareRuntimeCommandNames(t *testing.T) {
-	for _, name := range []string{"serve", "migrate", "migrate:rollback", "migrate:status", "build", "dev"} {
+	for _, name := range []string{"serve", "migrate", "migrate:rollback", "migrate:status", "build", "dev", "new"} {
 		if _, err := NewRoot("app", []Command{{Name: name}}, io.Discard); err != nil {
 			t.Fatalf("%s: %v", name, err)
 		}