goperf evidence

Per-rule <slug>.md + <slug>.jsonl for the original five rules (gp-make-hot–gp-defer-hot), measured with examples/bench/evidence_gp.go. gp-regexp-compile-hot, gp-json-marshal-hot, and gp-reflect-hot have JSONL microbenches and stay hint. gp-reflect-hot matches name lookup and reflect.New (a TypeOf rerun was about 1.3× and is not matched). gp-time-parse-in-loop was removed. Defaults are unchanged: gp-make-hot–gp-fmt-hot off, gp-append-nil-slice/gp-defer-hot hint.

See ../docs/evidence-policy.md and root docs/rule-regression.md.