v5.6.1

Two things that compiled and then did not work in the browser.

Fixes

• A resource read in a label follows the resource. Whether text or an
  attribute is drawn live was decided by the reads a state compiles to, and
  a resource's or a connection's values are read through its handle, so a
  label that read only one was worked out once, while it was loading:
  Button(if plan.data != null { "Request approval" } else { "Deploy" })
  stayed "Deploy" after the plan arrived, and Text("{rows.state}") stayed
  "loading". name.state, .data, .error and a connection's .messages
  are now live in text, a splice and an attribute alike.
• A list's key may read the index. for e, n in list by n threw before
  the list drew (_n is not defined), and wf check passed: the key was
  compiled with the item alone. It is given the item and the index, so by n works and so does by "{e.id}-{n}" — though a key of the index alone
  moves with the position, and keeps nothing across an insert.

Upgrading

Nothing to change. A derived value written only to make a resource's
label live can go back into the label.

Full Changelog: v5.6.0...v5.6.1