Function skirmishIncome

skirmishIncome(
    state: SkirmishState,
    owner: string,
    baseIncome: number,
    perVillage: number,
): number
Net income for one side, from a flat base plus every village it currently owns - purely a function of the map's own village ownership, no formula beyond that belongs here, the same policy board.Army's armyIncome already follows.
Parameters
- state: SkirmishState
- owner: string
- baseIncome: number
- perVillage: number
Returns number
Example
```
import { startingSkirmish, setSkirmishTerrain, skirmishIncome } from '@datamoc/mw_games/board';

const state = startingSkirmish(4, 1, { plain: { moveCost: 1, defense: 0 } });
setSkirmishTerrain(state, 0, 0, 'plain', true);
state.cells[0].owner = 'blue';

console.log(skirmishIncome(state, 'blue', 2, 1)); // 3 - base 2, plus 1 for the one village
```
- Defined in src/board/HexSkirmish.ts:293