Remove dependncy on GPKG driver for GDAL

Less dependencies is always good, this one was hardly being used.

kart/tabular/working_copy/gpkg.py

@@ -191,24 +191,10 @@ def status(self, check_if_dirty=False, allow_unconnectable=False):
         return result
 
     def create_and_initialise(self):
-        # GDAL: Create GeoPackage
-        # GDAL: Add metadata/etc
-        gdal_driver = gdal.GetDriverByName("GPKG")
-        gdal_ds = gdal_driver.Create(str(self.full_path), 0, 0, 0, gdal.GDT_Unknown)
-        del gdal_ds
-
         with self.session() as sess:
-            # Remove placeholder stuff GDAL creates
-            sess.execute(
-                "DELETE FROM gpkg_geometry_columns WHERE table_name='ogr_empty_table';"
-            )
-            sess.execute(
-                "DELETE FROM gpkg_contents WHERE table_name='ogr_empty_table';"
-            )
-            sess.execute("DROP TABLE IF EXISTS ogr_empty_table;")
-
-            # Create metadata tables
+            # Create standard GPKG tables:
             GpkgTables().create_all(sess)
+            # Create Kart-specific tables:
             self.kart_tables.create_all(sess)
 
     def _create_table_for_dataset(self, sess, dataset):

kart/tabular/working_copy/table_defs.py

@@ -13,15 +13,18 @@
 
 
 class TinyInt(Integer):
-    __visit_name__ = "TINYINT"
+    def visit(self):
+        return "TINYINT"
 
 
 class Double(Float):
-    __visit_name__ = "DOUBLE"
+    def visit(self):
+        return "DOUBLE"
 
 
 class DateTime(Text):
-    __visit_name__ = "DATETIME"
+    def visit(self):
+        return "DATETIME"
 
 
 STATE = "state"
@@ -183,7 +186,7 @@ def __init__(self):
             Column(
                 "srs_id",
                 Integer,
-                ForeignKey("gpkg_spatial_ref_sys.srd_id", name="fk_gc_r_srs_id"),
+                ForeignKey("gpkg_spatial_ref_sys.srs_id", name="fk_gc_r_srs_id"),
             ),
         )