fix(detector): detect descriptor input float passthrough

[prasannakotyal]

Summary

• extend INPUT_PASSTHROUGH_OUTPUT to descriptor-backed fake output wrappers
• detect descriptors whose __get__ returns owner.<stored_input>.float()
• require a wrapper class to store the entrypoint input into that attribute and the entrypoint to return the descriptor access directly

Target

KernelGuard-Red-Submission: 100

Validation

• UV_CACHE_DIR=/tmp/uvcache uv run python -m py_compile kernelguard.py
• descriptor wrapper _W(data).d returning data.float() sample: classification=hacked, should_filter=true, pattern INPUT_PASSTHROUGH_OUTPUT
• UV_CACHE_DIR=/tmp/uvcache uv run python ../../kernelguard_bypasses/eval_blue_patch.py kernelguard.py clean fixtures remain should_filter=False
• __init_subclass__ extension passed official eval on PR fix(detector): detect init-subclass input float passthrough #247 with TP 20/20, FP 20/20, surgicalness 1.0

[github-actions]

KernelGuard Blue Evaluation

• Evaluation job: 193
• Blue submission: 165
• Result: passed
• Target red submission caught: True
• Validation suite: TP 20/20, FP 20/20
• Surgicalness score: 1.0
• Workflow run: https://github.com/SinatrasC/kernelguard/actions/runs/25382661879