feat: act_as_user_id service delegation (v0.5.0)

[artugro]

Summary

Adds `act_as_user_id` kwarg to both clients so internal services (wisdom-agents, hosting multi-tenant entities) can operate on behalf of specific users without holding user-scoped API keys.

Closes: #25

Paired with:

• wisdom-side auth dep (`get_current_user_or_service`) — IntunoAI/intuno#38 (PR #37 updated with this commit)
• wisdom-agents switch to service client — IntunoAI/wisdom-agents#79

What changes

• `IntunoClient` / `AsyncIntunoClient` accept optional `act_as_user_id: UUID | str | None`
• When set, the client sends `X-Service-Key: <api_key>` + `X-On-Behalf-Of: ` instead of the normal `X-API-Key` / `Bearer` header
• Mutually exclusive — delegation mode never mixes the two auth headers
• Version bump: 0.4.0 → 0.5.0 (MINOR, additive)

Test plan

• 4 new unit tests covering normal mode, delegation with UUID, delegation with string user_id, async delegation
• All 42 pre-existing tests still pass (46 total now)
• Smoke: `IntunoClient(api_key='secret', act_as_user_id=uuid)` \u2014 correct headers

Usage

from uuid import UUID
from intuno_sdk import AsyncIntunoClient

# Normal end-user flow (unchanged)
client = AsyncIntunoClient(api_key="wsk_user_key")

# Internal service (wisdom-agents)
client = AsyncIntunoClient(
    api_key=settings.AGENTS_SERVICE_API_KEY,
    act_as_user_id=UUID("..."),  # the entity's owner
)

🤖 Generated with Claude Code