Rename @reviq/utils to @reviq/server-utils and add package READMEs

- Rename packages/utils/ to packages/server-utils/
- Update all imports and package.json references
- Add READMEs for frontend-utils, server-utils, and common packages
- Update main README with new package structure

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

README.md

@@ -26,9 +26,11 @@ A modern publisher dashboard for managing organizations, members, and sites. Bui
 
 ### Shared Packages
 - `@reviq/api-contract` - Shared API contract (oRPC)
+- `@reviq/common` - Shared utilities for frontend and backend
 - `@reviq/db` - Database client and queries
 - `@reviq/db-schema` - Database schema and codegen
-- `@reviq/utils` - Shared utilities
+- `@reviq/frontend-utils` - Frontend-specific utilities
+- `@reviq/server-utils` - Server/CLI utilities
 
 ## Project Structure
 
@@ -40,10 +42,12 @@ publisher-dashboard/
 │   └── publisher-dashboard/  # SvelteKit frontend
 ├── packages/
 │   ├── api-contract/      # Shared oRPC contract
+│   ├── common/            # Shared utilities (frontend + backend)
 │   ├── db/                # Database client
 │   ├── db-schema/         # DB schema & codegen
-│   ├── testing/           # Test utilities
-│   └── utils/             # Shared utilities
+│   ├── frontend-utils/    # Frontend utilities
+│   ├── server-utils/      # Server/CLI utilities
+│   └── testing/           # Test utilities
 └── db/                    # Database migrations
 ```