UX-77: Home's roll shares the peak room by room left to full, as control does

The cheap-run roll (cheaproll._Charge) shared the peak room by rating, control
shares it by room left to full (packshare.weights). With unequal levels one
battery's drawn block ended too early (rig F-1). The roll now uses
packshare.weights over the simulated levels, each battery capped at its rating,
a full one dropping out. test_ux77 gains two unequal-level walks and a
by-rating mutant; its walks model control's split by room too.

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

goodwe_controller/DECISIONS/UX-54-forecast-tab.md

@@ -101,8 +101,9 @@ is `SolarToday.add()` after the solar read, in a `try`, in memory.
   control will stop charging, as the tab does for tomorrow's: the cheap run
   rolls on at its end while a battery is short (`cheaproll.roll_end()`, the
   same loop as `dayview._levels()`), the level read at the charge power the
-  peak limit leaves (peak aim less the house, else the rating), and each
-  battery's block ends at its own stop. The curve stops charging at its level
+  peak limit leaves (peak aim less the house, else the rating) and shared by
+  room left to full as control shares it (`packshare.weights()`, re-read as
+  the levels move), and each battery's block ends at its own stop. The curve stops charging at its level
   (`charge_to()`) and giving at the floor.
 - Today, a give run in the plan on a battery that is empty now has no block on
   Home (no energy to give). The tab equals Home, and says so: "The add-on plans