Contracts aren't synced when we come back online

[taoeffect]

Problem

Related to this Review: #2660 (comment)

Contracts are not sync'd when we come back online. It was thought that this happened here in chelonia.js:

        'subscription-succeeded': (event) => {
          const { channelID } = event.detail
          if (this.subscriptionSet.has(channelID)) {
            // For new subscriptions, some messages could have been lost
            // between the time the subscription was requested and it was
            // actually set up. In these cases, force sync contracts to get them
            // updated.
            sbp('chelonia/private/out/sync', channelID, { force: true }).catch(err => {
              console.warn(`[chelonia] Syncing contract ${channelID} failed: ${err.message}`)
            })
          }
        }

But this 'subscription-succeeded' is the wrong event.

So for example, as mentioned in the review, being offline and someone changing their display name, then coming back online, doesn't show the change.

Solution

Listen to the correct event, the one for when we come back online.