Implement slog.LogValuer

[nozo-moto]

#107

This change is 

code

package main

import (
	"context"
	"log/slog"
	"os"

	"github.com/cockroachdb/errors"
)

func f1() error {
	return errors.Wrap(f2(), "wrapped error 1")
}

func f2() error {
	return errors.Wrap(f3(), "wrapped error 2")
}

func f3() error {
	return errors.Wrap(f4(), "wrapped error 3")
}

func f4() error {
	return errors.Wrap(f5(), "wrapped error 4")
}

func f5() error {
	return errors.New("error root")
}

func main() {
	ctx := context.Background()
	err := f1()

	logger := slog.New(slog.NewJSONHandler(os.Stdout, nil))
	logger.InfoContext(ctx, "test", slog.Any("error", err))
}

result

{
  "time": "2023-09-18T17:57:09.438517+09:00",
  "level": "INFO",
  "msg": "test",
  "error": {
    "message": "wrapped error 1: wrapped error 2: wrapped error 3: wrapped error 4: error root",
    "stacktrace": {
      "main.f1": {
        "file": "/Users/nozo/tmp/cockloaddb-slog-try/main.go",
        "name": "main.f1",
        "line": 12
      },
      "main.main": {
        "file": "/Users/nozo/tmp/cockloaddb-slog-try/main.go",
        "name": "main.main",
        "line": 33
      },
      "runtime.main": {
        "file": "/opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/proc.go",
        "name": "runtime.main",
        "line": 267
      },
      "runtime.goexit": {
        "file": "/opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/asm_arm64.s",
        "name": "runtime.goexit",
        "line": 1197
      }
    }
  }
}

[cockroach-teamcity]

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