fix: update refresh token TTL to 30 days

[nnnkkk7]

fix #1579

• Changed default refresh token TTL from 1 hour to 30 days
• Added explicit WithRefreshTokenTTL() in service initialization

In the generateToken function, there was logic to set a default 30-day TTL but override it with the options value if present:

refreshTokenTTL := 30 * day
if s.opts.refreshTokenTTL > 0 {
    refreshTokenTTL = s.opts.refreshTokenTTL
}

However, the defaultOptions had the refresh token TTL set to just 1 hour:

var defaultOptions = options{
    refreshTokenTTL: time.Hour,
    logger:          zap.NewNop(),
}

And the service initialization did not explicitly specify the WithRefreshTokenTTL option, so the default 1-hour value was used.

The condition if s.opts.refreshTokenTTL > 0 was always true, causing the default 30-day setting to always be overridden with the 1-hour value.

[cre8ivejp]

Instead of passing a fixed value here, how about implementing it as a config value being passed using flags?
This way, the user can set what is best for him when hosting the project.

E.g.

refreshTokenTTL: cmd.Flag("refresh-token-ttl", "refresh token ttl").Default("168h").Duration() // 7 days

[nnnkkk7]

I see. Thank you!
Is it ok ? feat: add refresh token TTL config