UX-13 P4: the setup wizard for installers

The Setup tab draws the Installer view's page model one step at a time,
from each field's `wizard` step in app/uilayout.py: meter (with the kettle
test), inverters and batteries, solar (optional), prices, peak limit
(battery modes: "comes in a later update", OPT-11), check and start.
It reuses P2's controls and saves through /config/validate and
/config/save. No route was added.

- First run: /config/model says `setup_needed` when the stored options name
  no power request entity, or on a new install (no `setup_done` and no
  `auto` in the Store, control not started). The page opens #setup only
  when opened with no route. The wizard's save writes `setup_done`.
- Kettle test: GET ha/entities?entity= reads one entity now, in W. The
  change decides: up keeps meter_invert off, down turns it on; a net or
  import/export meter that goes down blocks the step with what to check.
- Last step: validate.setup_checks() beside the refusals: the meter reads,
  each power request entity exists in HA (bad if not, SAFETY-77), battery
  levels and power with direction, solar sign, prices. Saves with
  shadow_mode on by default, then a confirmed restart naming the 0 W.
- P2 test finding (a): a stale save lists only the keys the other surface
  moved (the blob handed out on open, by fingerprint, against stored now).
- test_setup.py; tools/ux13_wizard_blobs.py makes the 88 blobs the wizard
  can save; all accepted by Supervisor 2026.08.0 AppOptions (offline).
- DECISIONS/UX-13-setup-wizard.md; DOCS "Setup, for a new install".

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LyR88rXETvwhTgx6yHE39p

goodwe_controller/app/static/index.html

@@ -117,11 +117,18 @@
 </section>
 
 <section class="screen" id="s-wiz" role="tabpanel" aria-labelledby="t-wiz" hidden>
-  <div class="card">
-    <h2 data-t="setup.name"></h2>
-    <p class="small muted" data-t="setup.description"></p>
-    <a class="btn" href="config" data-t="settings.open"></a>
+  <div class="card" id="wz">
+    <div class="row spread"><h2 id="wz-title" style="margin:0" data-s="setup.name"></h2><span class="tiny muted" id="wz-count"></span></div>
+    <div class="steps" id="wz-steps" aria-hidden="true"></div>
+    <p class="small muted" id="wz-desc" style="margin:0 0 6px"></p>
+    <div id="wz-banner" aria-live="polite"></div>
+    <div id="wz-body"><p class="small muted" data-s="loading"></p></div>
+    <div class="row spread" id="wz-nav" style="margin-top:14px">
+      <button class="btn" id="wz-back" type="button" data-s="setup.back"></button>
+      <button class="btn primary" id="wz-next" type="button" data-s="setup.next"></button>
+    </div>
   </div>
+  <p class="tiny muted" data-s="setup.description"></p>
 </section>
 </main>