build: add production robot profile

[jaagut]

Summary

Add an explicit production-oriented robot build profile and make it measurable in the same CI benchmark.

Proposed changes

• Build the robot environment as RelWithDebInfo.
• Disable test target generation for robot builds.
• Add a CI-compatible benchmark task with the same production settings while continuing to skip packages that require the proprietary ZED SDK.
• Let the benchmark script select the Pixi build task and record that task in its JSON and step summary.

Impact

Robot deployments avoid configuring and compiling test targets while retaining optimized binaries and debug information. CI continues to use its normal test-enabled build outside the dedicated benchmark workflow.

Stack

This PR is based on agent/build-benchmark-ccache.

Validation

• pixi run -e default ruff check scripts/benchmark_build.py
• pixi run -e default ruff format --check scripts/benchmark_build.py
• Parsed pixi.toml and listed the new Pixi task.
• Built bitbots_head_mover successfully with the production robot profile.
• git diff --check

Hardware runtime and build-time validation on a robot remains a follow-up after the CI comparison.