fix: protocol 2 core review findings

From the review of #99:
- A sync could stall when a client took a slot the moment another left:
  loop() used up the new client's sync on the old one. The slots move
  to ProtoSlots, a pure module with native tests, and loop() takes a
  slot's wants only for the client it read (takeWants).
- Deleting a group sends its shades, whose inGroup changed. Deleting a
  shade unlinks it from its groups and sends them, so a new shade given
  its id doesn't join them.
- next and sync with an id get an ok reply, and a message in pieces
  gets one bad request, not one per piece.
- Feeds check for loop() before they write the event buffer, and log
  an event too large, as events do.
- editChanges() (ModelEditor, native tests) says what clients get after
  an edit; the edit result carries the shade a group gained or lost.
  order() takes a sort_list_t.
- The frame writers move to ProtoFrame. Renames: pf to proto_field_t,
  the X-macro letters to TYPE/FIELD/ERR/FEED, proto_request_t to
  proto_message_t, REQ_* to WANTS_*, fmt to eventJson. The event
  bodies share sendItem(), the connection type name lives in
  ESPNetwork, and the loop() task check in SocketEmitter.
- e2e: the heap floor check skips when the low since boot is already
  under it; tests for replies to next and sync and a long message.
- SECURITY_PLAN.md splits step 1 into 1a-1d.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

test/test_modeleditor/test_modeleditor.cpp

@@ -134,6 +134,66 @@ static void test_255_means_no_pin() {
   TEST_ASSERT_EQUAL_INT8(0, conflict(shade_types::roller, radio_proto::GP_Remote, 255, 26, 255));
 }
 
+/*********************************************************************
+ * What protocol 2 clients are sent after an edit
+ ********************************************************************/
+static edit_result_t resultFor(uint8_t id, uint8_t shadeId = 0) {
+  edit_result_t r;
+  r.id = id;
+  r.shadeId = shadeId;
+  return r;
+}
+static void test_a_shade_edit_sends_the_whole_shade() {
+  const model_edit_type_t types[] = {
+    model_edit_type_t::add_shade, model_edit_type_t::save_shade, model_edit_type_t::set_paired,
+    model_edit_type_t::link_remote, model_edit_type_t::unlink_remote
+  };
+  for(model_edit_type_t t : types) {
+    const edit_changes_t c = editChanges(t, resultFor(7));
+    TEST_ASSERT_EQUAL_UINT8(7, c.shadeId);
+    TEST_ASSERT_EQUAL_UINT8(0, c.groupId);
+    TEST_ASSERT_EQUAL_UINT8(0, c.roomId);
+  }
+}
+static void test_a_group_edit_sends_the_whole_group() {
+  TEST_ASSERT_EQUAL_UINT8(3, editChanges(model_edit_type_t::add_group, resultFor(3)).groupId);
+  TEST_ASSERT_EQUAL_UINT8(3, editChanges(model_edit_type_t::save_group, resultFor(3)).groupId);
+}
+static void test_linking_a_shade_to_a_group_sends_both() {
+  // The shade's inGroup changes with the group's shades.
+  for(model_edit_type_t t : {model_edit_type_t::link_to_group, model_edit_type_t::unlink_from_group}) {
+    const edit_changes_t c = editChanges(t, resultFor(3, 9));
+    TEST_ASSERT_EQUAL_UINT8(3, c.groupId);
+    TEST_ASSERT_EQUAL_UINT8(9, c.shadeId);
+  }
+}
+static void test_a_room_edit_sends_the_room() {
+  TEST_ASSERT_EQUAL_UINT8(2, editChanges(model_edit_type_t::add_room, resultFor(2)).roomId);
+  TEST_ASSERT_EQUAL_UINT8(2, editChanges(model_edit_type_t::save_room, resultFor(2)).roomId);
+}
+static void test_a_sort_edit_sends_its_list() {
+  TEST_ASSERT_EQUAL(sort_list_t::rooms, editChanges(model_edit_type_t::room_order, resultFor(0)).order);
+  TEST_ASSERT_EQUAL(sort_list_t::shades, editChanges(model_edit_type_t::shade_order, resultFor(0)).order);
+  TEST_ASSERT_EQUAL(sort_list_t::groups, editChanges(model_edit_type_t::group_order, resultFor(0)).order);
+  TEST_ASSERT_EQUAL(sort_list_t::none, editChanges(model_edit_type_t::save_shade, resultFor(1)).order);
+}
+static void test_a_repeater_edit_sends_the_repeaters() {
+  TEST_ASSERT_TRUE(editChanges(model_edit_type_t::link_repeater, resultFor(0)).repeaters);
+  TEST_ASSERT_TRUE(editChanges(model_edit_type_t::unlink_repeater, resultFor(0)).repeaters);
+  TEST_ASSERT_FALSE(editChanges(model_edit_type_t::save_room, resultFor(1)).repeaters);
+}
+static void test_deletes_send_nothing_more() {
+  // Their removals go out as they happen.
+  for(model_edit_type_t t : {model_edit_type_t::delete_room, model_edit_type_t::delete_shade, model_edit_type_t::delete_group}) {
+    const edit_changes_t c = editChanges(t, resultFor(4));
+    TEST_ASSERT_EQUAL_UINT8(0, c.shadeId);
+    TEST_ASSERT_EQUAL_UINT8(0, c.groupId);
+    TEST_ASSERT_EQUAL_UINT8(0, c.roomId);
+    TEST_ASSERT_EQUAL(sort_list_t::none, c.order);
+    TEST_ASSERT_FALSE(c.repeaters);
+  }
+}
+
 int main(int argc, char **argv) {
   (void)argc;
   (void)argv;
@@ -157,5 +217,12 @@ int main(int argc, char **argv) {
   RUN_TEST(test_a_pin_another_shade_uses);
   RUN_TEST(test_only_the_pins_a_shade_drives_are_checked);
   RUN_TEST(test_255_means_no_pin);
+  RUN_TEST(test_a_shade_edit_sends_the_whole_shade);
+  RUN_TEST(test_a_group_edit_sends_the_whole_group);
+  RUN_TEST(test_linking_a_shade_to_a_group_sends_both);
+  RUN_TEST(test_a_room_edit_sends_the_room);
+  RUN_TEST(test_a_sort_edit_sends_its_list);
+  RUN_TEST(test_a_repeater_edit_sends_the_repeaters);
+  RUN_TEST(test_deletes_send_nothing_more);
   return UNITY_END();
 }