feat(config): enable Go2 manager pd gain event

[TATP-233]

Summary

• add factory-owned pd_gains to the unregistered Go2 Manager-Based pilot
• use community abs semantics with the legacy 35/0.5 ±10% gain ranges because the model default actuator kd is zero
• remove test-side event injection; real MuJoCo/Motrix reset evidence now consumes the factory unchanged

Refs #1094
Umbrella #1042

Scope

• 2 files
• 18 additions / 11 deletions / 7 net lines
• no production registry, Hydra, legacy DR, backend contract, runner, or IPC changes

Validation

• make test-all: 2019 passed, 27 skipped, 276 deselected, 1 xfailed
• ruff, mypy, pyright, coverage suite, and benchmark smoke passed
• remote CI intentionally skipped per Roadmap: 将 UniLab 迁移为社区通用的 Manager-Based API #1042