Add tests for Computer Use tool when API becomes available

[evansenter]

Summary

The with_computer_use() and with_computer_use_excluding() builder methods exist but have no integration tests.

Current State

• with_computer_use() - implemented in src/request_builder/mod.rs:1443
• with_computer_use_excluding() - implemented in src/request_builder/mod.rs:1493
• Wire format marked as UNVERIFIED in docs/ENUM_WIRE_FORMATS.md
• No tests exist

Why Blocked

Computer Use has limited API access and the wire format is unverified. We need:

1. API access to test against
2. Verification of the wire format with LOUD_WIRE=1

When to Unblock

• When Google makes Computer Use generally available
• When we can verify the wire format

Action Items

• Verify wire format with LOUD_WIRE=1 when available
• Add unit tests for builder methods
• Add integration test demonstrating usage
• Update docs/ENUM_WIRE_FORMATS.md with verified format

[evansenter]

Audit Update (2026-03-28)

Stale References

The methods referenced in this issue were refactored in PR #382 (unified tool config API):

• with_computer_use() → add_tool(ComputerUseConfig::new())
• with_computer_use_excluding() → add_tool(ComputerUseConfig::new().excluding(vec![...]))

Already Completed

• ✅ Unit tests for builder methods — Exist in src/request_builder/tests.rs:239-248 (tests add_tool with ComputerUseConfig) and src/tools.rs (serialization tests for ComputerUseConfig)

Still Remaining

• Verify wire format with LOUD_WIRE=1 when API becomes available
• Add integration test demonstrating usage
• Update docs/ENUM_WIRE_FORMATS.md with verified format