docs+tool: locate & extract world factory production-line recipes

The fixed single-recipe world structures (conveyors, e.g. 1 Raw Aurogen
Crystal -> 10 Energy Rods) are a separate mechanic from workbench recipes.
Document where they live and how to read them, with a reproducible extractor.

- docs/PRODUCTION_LINES.md: the 'where to find it' record — ECS classes
  (ProductionLineRecipeComponent -> CraftingRecipe), the epb_assets_all
  game_conveyor_*_epb prefabs, EntityBlueprint/Odin serialization, the
  extraction path, and the open energy_grid_*/island-placement lead.
- bundle/extract_production_lines.py: UnityPy + odin_read extractor ->
  extracted/production_lines.json (14 conveyor recipes).
- BUNDLES.md: add production_lines.json to the data-source map.

BUNDLES.md

@@ -11,7 +11,8 @@ Read the bundles in Python with `bundle/extract_data.py` / `loot_probe.py` (Unit
 | `extracted/` output | Source bundle | Asset |
 |---|---|---|
 | `items_registry.json` / `item_definitions.json` | `configuration` | `CheatItemDefinitionsData.asset` |
-| `crafting_recipes.json` | `craftingrecipes` | `Recipes_*` |
+| `crafting_recipes.json` | `craftingrecipes` | `Recipes_*` (workbench) |
+| `production_lines.json` | `epb` | `game_conveyor_*_epb` (world factories) — see [docs/PRODUCTION_LINES.md](docs/PRODUCTION_LINES.md) |
 | `loot_tables.json` | `configuration` | `conf_worldLootTables{Storm,Voyage}Config` (Odin-binary) |
 | `CompartmentsDatabase.json` | `walkershared` | `CompartmentsDatabase.json` (TextAsset) |
 | `epb_catalog.json` | `epb` | `*_epb.prefab` |