Added option to highlight your own messages (#3833)

* Removed magic numbers when checking rowIndex

* Swap from static ints to enum

* Referred enum members by enum name

* Fixed formatting

* Added highlight option for self messages

* Update CHANGELOG.md

* Made disabled by default

* Moved setting from Messages tab to Users tab

* Moved checks to HighlightController

* Set row index to 0

sillE silly me

* Update CHANGELOG.md

* Moved check outside of loop

* Improved naming and documentation on variables

* Fixed formatting

* Fix compile errors

* Update ColorProvider self message highlight color when it's changed

Use the ColorProvider self message highlight color instead of rolling
our own non-updating color

* Update changelog entry

* Remove unused `customColor` from user highlights builder

* Use explicit lambda capture

* Update comment for the color provider color

* HighlightModelHpp: Future-proof custom row enum B)

* Document UserHighlightModel color changes

* Update colorprovider comment

* Update enabled, show in mentions & color setting paths

* Rename settings from `selfMessagesHighlight` to `selfMessageHighlight`

---------

Co-authored-by: Rasmus Karlsson <rasmus.karlsson@pajlada.com>

src/singletons/Settings.hpp

@@ -288,6 +288,13 @@ public:
     QStringSetting selfHighlightColor = {"/highlighting/selfHighlightColor",
                                          ""};
 
+    BoolSetting enableSelfMessageHighlight = {
+        "/highlighting/selfMessageHighlight/enabled", false};
+    BoolSetting showSelfMessageHighlightInMentions = {
+        "/highlighting/selfMessageHighlight/showInMentions", false};
+    QStringSetting selfMessageHighlightColor = {
+        "/highlighting/selfMessageHighlight/color", ""};
+
     BoolSetting enableWhisperHighlight = {
         "/highlighting/whisperHighlight/whispersHighlighted", true};
     BoolSetting enableWhisperHighlightSound = {