Added IconsHelper and updated Keyboard to support require_inside flag

tests/controls/test_icons_helper.py

@@ -0,0 +1,23 @@
+from myfasthtml.controls.IconsHelper import IconsHelper
+
+
+def test_existing_icon():
+  IconsHelper.reset()
+  assert IconsHelper.get(True) is not None
+
+
+def test_dynamic_icon():
+  IconsHelper.reset()
+  assert IconsHelper.get("add20_filled") is not None
+
+
+def test_unknown_icon():
+  IconsHelper.reset()
+  assert IconsHelper.get("does_not_exist") is None
+  
+
+
+def test_dynamic_icon_by_package():
+  IconsHelper.reset()
+  assert IconsHelper.get("add20_filled", "fa") is None
+  assert IconsHelper.get("add20_filled", "fluent") is not None