Update the Firehouse Chat app

[heyjay44]

What success looks like:

• compatible with 0.19
• adapt to fireproof/cloud

[mabels]

retest @mschoch with 0.19.112

[mschoch]

• I have confirmed that the previous build problem I had encountered has been resolved
• However, progress has been slower than anticipated due to the following:
  • Project was initialized from the partykit template, so by removing partykit, we're removing all the project infrastructure (build, preview etc all used partykit cmdline). This aspect of the project has to be redone.
  • Still struggling to grok the app enough to start ripping things out

[heyjay44]

Issue with useLiveQuery