Rename Hightower components to Trebuchet

- Rename npm packages: @shannon/api -> @trebuchet/api, @shannon/worker -> @trebuchet/worker, @keygraph/shannon -> @trebuchet/cli
- Update CLI references from shannon/keygraph to trebuchet/trebuchet
- Update Dockerfile and CLAUDE.md to reflect new package names
- Update TypeScript imports in API to use @trebuchet/worker

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/worker/package.json

@@ -1,5 +1,5 @@
 {
-  "name": "@shannon/worker",
+  "name": "@trebuchet/worker",
   "version": "0.0.0",
   "private": true,
   "type": "module",