Significant work done porting to headless engine

procedural/src/engine/support/features_external.md

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+# External Dependencies for features.js
+
+The refactored `features.js` module requires the following external dependencies to be imported:
+
+## Module Dependencies
+
+### `Lakes` module
+- **Functions used:**
+  - `Lakes.getHeight(feature)` - Calculate height for lake features
+  - `Lakes.getName(feature)` - Generate names for lake features
+
+## Utility Functions Required
+
+The following utility functions need to be passed via the `utils` parameter:
+
+### Core Utilities
+- `INT8_MAX` - Maximum value for Int8 arrays
+- `rn(value)` - Rounding function
+- `isLand(cellId)` - Check if a cell is land
+- `isWater(cellId)` - Check if a cell is water
+- `dist2(point1, point2)` - Calculate squared distance between two points
+- `clipPoly(vertices)` - Clip polygon vertices
+- `unique(array)` - Remove duplicates from array
+- `createTypedArray({maxValue, length})` - Create appropriately typed array
+- `connectVertices({vertices, startingVertex, ofSameType, closeRing})` - Connect vertices to form paths
+
+### D3.js Integration
+- `d3.polygonArea(points)` - Calculate polygon area (accessed via `utils.d3.polygonArea`)
+
+## Configuration Dependencies
+
+The following configuration values need to be passed via the `config` parameter:
+
+### Timing and Randomization
+- `TIME` - Boolean flag to enable/disable timing logs
+- `seed` - Random seed value for reproducible generation
+- `aleaPRNG` - Pseudo-random number generator function
+
+## Module Integration
+
+The module should be imported and used as follows:
+
+```javascript
+import { markupGrid, markupPack, specify } from './features.js';
+import { Lakes } from './lakes.js';
+
+// Usage example
+const updatedGrid = markupGrid(grid, config, utils);
+const updatedPack = markupPack(pack, grid, config, utils, { Lakes });
+const finalPack = specify(updatedPack, grid, { Lakes });
+```