benches: package as kernbench.benches, add @bench registry + list subcommand

Move benches/ -> src/kernbench/benches/ and src/kernbench/cli/probe.py ->
src/kernbench/probes/probe.py. Each bench self-registers via
@bench(name=..., description=...); kernbench list enumerates benches
with auto-assigned indices, --bench accepts kebab-case name or numeric
index. Audit at package-import time fails if any non-underscore module
forgets the decorator. ADR-0010 (EN + KO) updated to reflect the new
resolver path, list subcommand, and probes package separation.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tests/test_mmu_fabric.py

@@ -235,7 +235,7 @@ def test_qkv_gemm_still_passes():
         correlation_id="test_regression",
         spec=graph.spec,
     )
-    from benches.qkv_gemm import run as bench_run
+    from kernbench.benches.qkv_gemm import run as bench_run
     bench_run(ctx)
     ctx.wait_all()
     # If we get here without exception, the benchmark succeeded