pamhyr: Add just-in-time database geometry loading.

src/Model/Friction/FrictionList.py

@@ -68,6 +68,26 @@ class FrictionList(PamhyrModelList):
 
         return ok
 
+    def _get_frictions_list(self):
+        # Frictions list generator is type (int, Point) with the first
+        # element the index of the Point in list
+        return list(
+            map(
+                lambda p: p[1],
+                sorted(
+                    self._lst,
+                    key = lambda p: p[0]
+                )
+            )
+        )
+
+    @property
+    def lst(self):
+        if not isinstance(self._lst, list):
+            self._lst = self._get_frictions_list()
+
+        return self._lst
+
     @property
     def frictions(self):
         return self.lst