Micro-PR to add alt_atom_id to Biotite's internal CCD (#668)

* feat: add alt_atom_id to biotite's internal CCD

* fix: remove accidental duplicate block

* chore: ruff format

* fix: move `alt_atom_id` block below `atom_id`

setup_ccd.py

@@ -147,6 +147,22 @@ class ColumnInfo:
             )
         ],
     ),
+    "alt_atom_id": ColumnInfo(
+        "U6",
+        [
+            StringArrayEncoding(
+                # The unique strings in the column are sorted
+                # -> Indices do not follow distinct pattern
+                data_encoding=[ByteArrayEncoding(type=TypeCode.INT16)],
+                offset_encoding=[
+                    DeltaEncoding(src_type=TypeCode.INT32),
+                    RunLengthEncoding(),
+                    IntegerPackingEncoding(byte_count=1, is_unsigned=True),
+                    ByteArrayEncoding(),
+                ],
+            )
+        ],
+    ),
     "type_symbol": ColumnInfo(
         "U2",
         [