perf: only calculate average color once per tile

convert_heic.py

@@ -0,0 +1,18 @@
+from pathlib import Path
+from subprocess import run
+
+from send2trash import send2trash
+from tqdm import tqdm
+
+
+def main() -> None:
+    files = list(Path("tiles").glob("*.heic"))
+    with tqdm(files) as pbar:
+        for file in pbar:
+            pbar.set_description(f"Converting {file}")
+            run(("magick", file, file.with_suffix(".jpg")))
+            send2trash(file)
+
+
+if __name__ == "__main__":
+    main()