OPT-36 round 4: count only charge control will make; Solar first drain at the night base

Review F1: a slot after B's run counts only if no slot from the expensive
hours on is cheaper (control plans B's charge left in the cheapest window
ahead), and x 0.95 of B's charge is stored. Three-price night: 1ac7fe9 left
the expensive hours 2.61 kWh short; now 0.
Review F2: a Solar first battery's drain until the expensive hours reads each
hour at no less than the night base (the profile is net of the sun). Read net,
a dark morning drained the battery the plan still counted; A's level fell,
the cheap run moved and was lost before it started (+0.40 EUR per 3 days).
The two real-price replays now cost what 0.20.0 does.
F3: the ux54 sweep's peak limit is 15 kW (the option's top). F4: the rest
comes from the grid (EN/NL). F5: CHANGELOG and DECISIONS wording.

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

goodwe_controller/CHANGELOG.md

@@ -4,7 +4,7 @@
 
 ### Not in a release yet
 
-- Leftover solar no longer charges from the grid for hours that Cheap hours only or Solar first batteries will cover. It counts what they will hold when the expensive hours start (a Solar first battery after the night's use), and buys only the rest. The Batteries screen says which battery covers, and the "gives up to" figure is read after the planned charge.
+- Leftover solar now counts what Cheap hours only and Solar first batteries will still hold when the expensive hours start, and buys from the grid only the rest. The Batteries screen says when other batteries cover those hours.
 
 **A minor bump: a Forecast tab, a night grid charge sized to what the sun will not give, a kept evening forecast, and no option changes.**
 No option was added, removed or renamed, and no default changed (86 options). It is a minor bump because Leftover solar now buys different amounts from the grid and the night charge keeps its level when the forecast goes quiet; every saved setting still starts.