Scope policies and budgets by intent (not only agent)

[susheem-k]

Summary

Unclear / insufficient today whether policies are (or can be) scoped by intent. Intent is where product value concentrates: different jobs need different caps and behaviors. If policies are only global or per-agent, we miss the main lever.

Area: governance config, Store.governance_config_for, policy binding

Desired behavior

• Policies (and/or budgets) bindable by intent (alone or with agent), not only agent-wide defaults.
• Registration always carries a stable intent from the agent definition (see §1) so scoping is reliable.
• Admin / config UX makes intent-scoped rules first-class.

Acceptance sketch

• Same agent, two intents → different policy sets / budgets without forking agent code.
• Docs show intent-scoped config as the recommended model.

Reference: docs/notes/2026-07-23-design-fix-notes.md §3