Replace thirteenth battle map with hand-painted asset

docs/battle-map-terrain-atlas-pipeline.md

@@ -2,7 +2,7 @@
 
 ## Scope
 
-The first twelve campaign battles now use the same hand-painted tactical map pipeline. The renderer still reads the original scenario tile coordinates and battle logic; only the map texture asset changes from flat/vector map art to low-contrast raster terrain.
+The first thirteen campaign battles now use the same hand-painted tactical map pipeline. The renderer still reads the original scenario tile coordinates and battle logic; only the map texture asset changes from flat/vector map art to low-contrast raster terrain.
 
 ## Art Direction
 
@@ -29,6 +29,7 @@ python scripts/generate-handpaint-map-sample.py --map ninth --webp-quality 90
 python scripts/generate-handpaint-map-sample.py --map tenth --webp-quality 90
 python scripts/generate-handpaint-map-sample.py --map eleventh --webp-quality 90
 python scripts/generate-handpaint-map-sample.py --map twelfth --webp-quality 90
+python scripts/generate-handpaint-map-sample.py --map thirteenth --webp-quality 90
 ```
 
 ## Current Assets
@@ -45,6 +46,7 @@ python scripts/generate-handpaint-map-sample.py --map twelfth --webp-quality 90
 - `src/assets/images/battle/tenth-battle-map.webp`
 - `src/assets/images/battle/eleventh-battle-map.webp`
 - `src/assets/images/battle/twelfth-battle-map.webp`
+- `src/assets/images/battle/thirteenth-battle-map.webp`
 
 ## QA Outputs
 
@@ -70,5 +72,7 @@ python scripts/generate-handpaint-map-sample.py --map twelfth --webp-quality 90
 - `docs/eleventh-battle-map-handpaint-preview.png`
 - `docs/twelfth-battle-map-handpaint-before-after.png`
 - `docs/twelfth-battle-map-handpaint-preview.png`
+- `docs/thirteenth-battle-map-handpaint-before-after.png`
+- `docs/thirteenth-battle-map-handpaint-preview.png`
 
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