[FEATURE REQUEST]Support battery-only supply to home (no direct solar/grid to home lines)

[JordiGrasvi]

Feature Request: Support battery-only supply to home (no direct solar/grid to home lines)

Description

I would like to request a feature that allows configuring the energy flow so that:

• The battery can only be charged from solar and/or grid
• The home can only be supplied by the battery
• No direct flow lines are shown from solar → home or grid → home

This would be very useful for setups with portable power stations (e.g. Bluetti, Ecoflow, Jackery, etc.) where all loads are powered exclusively through the battery/inverter, and solar or grid are only charging inputs.

Current behavior
Even if solar/grid consumption entities are set to 0, the card still draws direct lines from solar → home and grid → home, which makes the diagram misleading for this type of setup.

Proposed solution
Add an option (e.g. force_battery_supply: true) so that the card only displays the following connections:

• Solar → Battery
• Grid → Battery
• Battery → Home

Benefit
This would make the card much more accurate and useful for portable power stations and hybrid setups where the battery is the only path to supply the home.

Thanks for considering!