OPT-11 P4: solar forecast and day plan

A Home Assistant solar forecast (Forecast.Solar, Solcast or Open-Meteo
shapes) and the add-on's own hourly house use decide, before each cheap
run, whether the sun will fill each battery before the expensive hours.
Leftover solar then buys from the grid only the shortfall; Cheap hours only
skips the part the sun covers; Solar first never grid-charges. No, stale or
failed forecast: P3 option A exactly (12 digests pinned from 5a4cdc2).

Replay (16 recorded days, forecast errors from Elia's day-ahead BE solar):
year-earlier prices P4 19.15 vs P2 19.33 / option A 19.44 / old trade 18.14;
real 2026 prices P4 29.19 vs 32.26 / 32.01 / 31.40 EUR net.

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

goodwe_controller/app/ui_text/en.json

@@ -119,7 +119,7 @@
     "description": "Every setting, grouped by task.",
     "view": {"name": "Settings view", "simple": "Simple", "installer": "Installer"},
     "simple": {"description": "The choices a home owner makes.",
-      "note": {"month_peak": {"description": "This month's peak so far: {kw}."}, "shadow": {"description": "Use Always on while you test a new installation."}},
+      "note": {"month_peak": {"description": "This month's peak so far: {kw}."}, "shadow": {"description": "Use Always on while you test a new installation."}, "forecast": {"description": "With a forecast, a battery buys only what the sun will not give."}},
       "batteries": {"name": "Batteries"},
       "more": {"description": "Looking for the meter, inverters or prices?"},
       "installer": "Open the installer view"},
@@ -334,8 +334,12 @@
       "saves": "Saves its power for {at}.",
       "saves_later": "Saves its power for higher prices.",
       "no_prices": "No prices, so it follows the house.",
-      "no_spread": "Prices differ too little, so it follows the house."
+      "no_spread": "Prices differ too little, so it follows the house.",
+      "sun_fills": "Enough sun is forecast, so it does not charge from the grid.",
+      "tops_up": "Too little sun is forecast, so it charges some from the grid.",
+      "no_forecast": "No solar forecast, so it charges from solar only."
     },
+    "solar": {"line": "Solar forecast today: {kwh}, we count on {count}. Updated {at}.", "no_forecast": "No solar forecast now, so Leftover solar charges from solar only.", "learning": "The add-on is learning your house's use. The plan starts tomorrow."},
     "today": {
       "not_planned": "Not planned yet.",
       "no_runs": "No cheap or expensive hours left today.",