docs: add comprehensive code comments, update README and TASKS, create training and troubleshooting guides

- Add JSDoc comments to API routes and business logic functions
- Update README.md with Phase 2 status and deployment/production notes
- Enhance TASKS.md with estimated timelines and dependencies
- Create docs/STAFF_TRAINING.md for team onboarding
- Create docs/CLIENT_ONBOARDING.md for customer experience
- Create docs/OPERATIONAL_PROCEDURES.md for daily operations
- Create docs/TROUBLESHOOTING.md for common setup issues
- Fix TypeScript errors in hq/page.tsx

lib/utils/short-id.ts

@@ -1,5 +1,8 @@
 import { supabaseAdmin } from '@/lib/supabase/client'
 
+/**
+ * generateShortId function that generates a unique short ID using Supabase RPC.
+ */
 export async function generateShortId(): Promise<string> {
   const { data, error } = await supabaseAdmin.rpc('generate_short_id')