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

go.work

@@ -0,0 +1,10 @@
+go 1.27.0
+
+toolchain go1.27.0
+
+use (
+	.
+	./examples/hello
+	./examples/hello/plugins/base
+	./examples/hello/plugins/greeter
+)