if (!user || typeof user.nam !== 'string') {
    throw new Error("Missing or invalid 'nam' on user");
  }

You really don't understand what types give you, do you?

Where are you going to put the code above in this:

  <section @name="user-details" class="user">

  <media :image="/app/icon/cc/{cc}.svg" :title="name">
    <p>{ email }</p>
  </media>

  <dl :if="org">
    <dt>Company</dt>      <dd>{ org }</dd>
    <dt>Country</dt>      <dd> { country }</dd>
    <dt>Company size</dt> <dd>{ size.desc } ({ size.label })</dd>
    <dt>Website</dt>      <dd><a class="action">{ website }</a></dd>
    <dt>Plan</dt>         <dd><pill icon="dot" :label="{ plan }"/></dd>
  </dl>

  <media-thumbs :items="shots"/>

  <chat-thread :thread="thread"/>

Are you going to write ifs for every permutation of possible typos? (Let's ignore for a second that it's not just typos)