adding slas clients and commands

[clavery]

Summary

Adds SLAS Admin API client and CLI commands for managing SLAS clients.

New CLI Commands

• slas client create - Create a new SLAS client with configurable scopes, channels, redirect URIs
• slas client get - Retrieve details of a specific SLAS client
• slas client list - List all SLAS clients for a tenant
• slas client update - Update an existing client (supports append/replace modes for list fields, secret rotation)
• slas client delete - Delete a SLAS client

SDK/Tooling Changes

• Added SLAS Admin API client (createSlasClient) using openapi-fetch with typed endpoints
• Added shared middleware for auth injection and request/response logging
• Added short-code flag to OAuthCommand and dw.json support (shortCode, short-code, scapi-shortcode)
• Documented API client creation conventions in clients/index.ts

Features

• All commands support --json flag for JSON output
• Auto-generates client ID (UUID) and name if not provided
• Secret generation with sk_ prefix for new clients
• Update command supports --replace to replace list values instead of appending

Testing

Manual testing against SLAS Admin API.

---

• Tests pass (pnpm test)
• Code is formatted (pnpm run format)