Add measured peak_ram_mb/peak_disk_mb; strip /swebench_matterhorn answer key; withdraw 5 leak-only-pass tasks (1322->1317)

task.toml: bare top-level cpus/memory matching SWE-Smith-Seeds-Clean consumer format; per-task timeout kept in [verifier]

1,322 oracle-verified, luna-n5-filtered, contamination-controlled SWE-rebench tasks (3 tiers)