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.gen.go

@@ -0,0 +1,14 @@
+// Code generated by summer build. DO NOT EDIT.
+
+package main
+
+import (
+	_ "git.golem15.com/golem15/summercms/examples/hello/plugins/base"
+	_ "git.golem15.com/golem15/summercms/examples/hello/plugins/greeter"
+)
+
+// PluginIDs is the ordered plugin list from summer.yaml.
+var PluginIDs = []string{
+	"golem15.hello",
+	"golem15.greeter",
+}