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>

scripts/gemm_sweep.py

@@ -117,19 +117,19 @@ def _run_one(M: int, K: int, N: int, topology: str, variant: str = "ref_ref") ->
     os.environ["MATMUL_N"] = str(N)
     os.environ["MATMUL_VARIANT"] = variant
 
-    # Late imports so env vars are read by benches/matmul_composite at module load.
+    # Late imports so env vars are read by matmul_composite at module load.
     # Force re-import to pick up new env values.
-    for mod_name in [m for m in list(sys.modules) if m.startswith("benches.matmul_composite")]:
+    for mod_name in [m for m in list(sys.modules) if m.startswith("kernbench.benches.matmul_composite")]:
         del sys.modules[mod_name]
 
-    from benches.loader import resolve_bench
+    from kernbench.benches.registry import resolve as resolve_bench
     from kernbench.runtime_api.bench_runner import run_bench
     from kernbench.runtime_api.types import resolve_device
     from kernbench.sim_engine.engine import GraphEngine
     from kernbench.topology.builder import resolve_topology
 
     topo = resolve_topology(topology)
-    bench = resolve_bench("matmul_composite")
+    bench = resolve_bench("matmul-composite").run
     device = resolve_device(None)
 
     t0 = time.time()