feat: add gen idea infra point

[9ssi7]

may close #1

intended useges

basic usage

package model

//go:generate rapidval -all $GOFILE
type User struct {
	ID       int64  `json:"id" validate:"min=1"`
	Username string `json:"username" validate:"required,min=3,max=50"`
	Email    string `json:"email" validate:"required,email"`
	Age      int    `json:"age" validate:"min=0,max=150"`
	IsActive bool   `json:"is_active"`
}

usage with easyjson

package model

//go:generate rapidval -all $GOFILE
//go:generate easyjson -all $GOFILE
type User struct {
	ID       int64  `json:"id" validate:"min=1"`
	Username string `json:"username" validate:"required,min=3,max=50"`
	Email    string `json:"email" validate:"required,email"`
	Age      int    `json:"age" validate:"min=0,max=150"`
	IsActive bool   `json:"is_active"`
}

its generates user_validate.go. Pre-defined validation function for model with validations as provided in struct tags.