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/api/src/services/temporal-client.ts

@@ -3,7 +3,7 @@
  * Uses @temporalio/client (not worker) since the API server only submits and queries workflows.
  */
 
-import type { PipelineProgress } from '@shannon/worker/pipeline';
+import type { PipelineProgress } from '@trebuchet/worker/pipeline';
 import { Client, Connection } from '@temporalio/client';
 
 export interface TemporalClients {

apps/api/src/types/api.ts

@@ -2,7 +2,7 @@
  * Request/response types and Zod validation schemas for the scan API.
  */
 
-import type { AgentMetrics, PipelineSummary } from '@shannon/worker/pipeline';
+import type { AgentMetrics, PipelineSummary } from '@trebuchet/worker/pipeline';
 import { z } from 'zod';
 
 // === Request Schemas ===