Scoped credentials and budget caps

What the copilot can do is bounded. Each agent gets its own scoped credentials for the tools it uses, held in a dedicated secrets store, and AI usage runs under per-tenant budget caps. Key points:

• Scoped credentials mean a mistake stays contained: one agent cannot borrow another's access, and the agent works with a reference, not a plaintext key.
• Per-tenant budget caps bound the spend, so runaway usage is gated rather than discovered on an invoice.