feat: rename remaining German API fields and deprecate legacy endpoints (#1164)

Complete the English API translation started in #675:

- rename input fields pv_akku to pv_battery and eauto to ev, and the
  solution fields eautocharge_hours_float to ev_charge_hours_float and
  eauto_obj to ev_obj; the German names are still accepted on input
  via validation aliases and re-emitted in responses as deprecated
  computed fields, same pattern as #675
- mark the legacy endpoints /strompreis, /gesamtlast and
  /gesamtlast_simple as deprecated in the OpenAPI schema
- use amount instead of a euro reference in the battery LCOS log
  message

Co-authored-by: Tobias Welz <tobias.wizneteu@gmail.com>

src/akkudoktoreos/server/eos.py

@@ -1173,7 +1173,7 @@ def fastapi_energy_management_plan_get() -> EnergyManagementPlan:
     return plan
 
 
-@app.get("/strompreis", tags=["prediction"])
+@app.get("/strompreis", tags=["prediction"], deprecated=True)
 async def fastapi_strompreis() -> list[float]:
     """Deprecated: Electricity Market Price Prediction per Wh [amount/Wh].
 
@@ -1236,7 +1236,7 @@ class GesamtlastRequest(PydanticBaseModel):
     hours: int
 
 
-@app.post("/gesamtlast", tags=["prediction"])
+@app.post("/gesamtlast", tags=["prediction"], deprecated=True)
 async def fastapi_gesamtlast(request: GesamtlastRequest) -> list[float]:
     """Deprecated: Total Load Prediction with adjustment.
 
@@ -1333,7 +1333,7 @@ async def fastapi_gesamtlast(request: GesamtlastRequest) -> list[float]:
     return prediction_list
 
 
-@app.get("/gesamtlast_simple", tags=["prediction"])
+@app.get("/gesamtlast_simple", tags=["prediction"], deprecated=True)
 async def fastapi_gesamtlast_simple(year_energy: float) -> list[float]:
     """Deprecated: Total Load Prediction.