Fix ATOMIC_REQUESTS incompatibility with async views

[7tg]

Summary

• Apply transaction.non_atomic_requests decorator to mcp_endpoint and MCPHTTPView async views, preventing Django from wrapping them in transaction.atomic() when ATOMIC_REQUESTS=True

Fixes #67

Test plan

• Verify mcp_endpoint has _non_atomic_requests attribute set for the default database
• Verify MCPHTTPView.as_view() has _non_atomic_requests attribute set for the default database
• All 380 tests pass, lint clean

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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