Companion module 0.1.5: settings save even before Resi answers

While the connection wasn't connected, nothing in its settings could be
saved. The saved decoder showed as "??" because the list only fills once
Resi answers, and a cue refresh that had never been saved showed as 0, below
its minimum. Either blocks Save, including the login change that would have
fixed the connection. That's how North Attleboro's connection stayed on a
locked login.

- The saved decoder is always a choice, "(not connected to Resi yet)" until
  Resi answers.
- An upgrade script fills settings an older connection never saved with
  their defaults (and leaves a complete one alone).
- Event details are read once per event instead of on every cue refresh:
  one Resi request fewer every few seconds on a shared account.
- Cue requests share the login/rate-limit hold-off; "Loaded N cues" and
  repeated cue-refresh failures are logged once, not every few seconds.
- "inf0" in the decoder info poll label.

source/config_test.js covers all of it (6 tests; the first fails on 0.1.4).
backoff_test.js 5/5 and the estimator matrix still pass.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

source/dist/config.js

@@ -48,7 +48,7 @@ function GetConfigFields() {
         {
             type: 'number',
             id: 'listPollMs',
-            label: 'User & decoder inf0 poll (ms)',
+            label: 'User & decoder info poll (ms)',
             width: 6,
             min: 10000,
             max: 3600000,