feat: safe timing helper

[Julien-R44]

Add safeTiming helper to prevent timing attacks by ensuring a callback always takes at least a minimum amount of time to execute.

import { safeTiming } from '@adonisjs/core/helpers'

return safeTiming(200, async () => {
  const user = await User.findBy('email', email)
  if (user) await sendResetEmail(user)
  return { message: 'If this email exists, you will receive a reset link.' }
})

supports returnEarly() to skip the delay when you want fast responses on success but constant time on failure

return safeTiming(200, async (timing) => {
  const token = await Token.findBy('value', request.header('x-api-key'))
  if (token) {
    timing.returnEarly()
    return token.owner
  }
  throw new UnauthorizedException()
})

inspired by laravel's timebox. Thought it was nice to have this in the core