feat(01-01): boot hello app and dispatch greeter:hello

- Add party plugin registry with Register-before-Boot activation
- Add backpack, compass, bonfire, and pact capability interfaces
- Add examples/hello with two compiled plugin modules

examples/hello/plugins/greeter/plugin.go

@@ -0,0 +1,43 @@
+package greeter
+
+import (
+	"context"
+
+	"git.golem15.com/golem15/summercms/backpack"
+	"git.golem15.com/golem15/summercms/bonfire"
+	"git.golem15.com/golem15/summercms/party"
+)
+
+// Plugin is the golem15.greeter plugin. It requires golem15.hello.
+type Plugin struct {
+	app *backpack.App
+}
+
+func (p *Plugin) ID() string         { return "golem15.greeter" }
+func (p *Plugin) Requires() []string { return []string{"golem15.hello"} }
+
+func (p *Plugin) Register(*backpack.App) error { return nil }
+
+func (p *Plugin) Boot(app *backpack.App) error {
+	p.app = app
+	return nil
+}
+
+func (p *Plugin) Commands() []bonfire.Command {
+	return []bonfire.Command{{
+		Name:        "greeter:hello",
+		Description: "Print the configured application name",
+		Run: func(ctx context.Context, in bonfire.Input, out bonfire.Output) error {
+			name := ""
+			if p.app != nil && p.app.Config != nil {
+				name = p.app.Config.String("app.name")
+			}
+			out.Println(name)
+			return nil
+		},
+	}}
+}
+
+func init() {
+	party.Register(&Plugin{})
+}