feat: add shared chat badge (#5661)

mocks/include/mocks/BaseApplication.hpp

@@ -3,6 +3,7 @@
 #include "common/Args.hpp"
 #include "mocks/DisabledStreamerMode.hpp"
 #include "mocks/EmptyApplication.hpp"
+#include "mocks/TwitchUsers.hpp"
 #include "providers/bttv/BttvLiveUpdates.hpp"
 #include "singletons/Fonts.hpp"
 #include "singletons/Settings.hpp"
@@ -55,6 +56,11 @@ public:
         return &this->fonts;
     }
 
+    ITwitchUsers *getTwitchUsers() override
+    {
+        return &this->twitchUsers;
+    }
+
     BttvLiveUpdates *getBttvLiveUpdates() override
     {
         return nullptr;
@@ -71,6 +77,7 @@ public:
     DisabledStreamerMode streamerMode;
     Theme theme;
     Fonts fonts;
+    TwitchUsers twitchUsers;
 };
 
 }  // namespace chatterino::mock

mocks/include/mocks/TwitchUsers.hpp

@@ -0,0 +1,24 @@
+#pragma once
+
+#include "providers/twitch/TwitchUser.hpp"
+#include "providers/twitch/TwitchUsers.hpp"
+
+namespace chatterino::mock {
+
+class TwitchUsers : public ITwitchUsers
+{
+public:
+    TwitchUsers() = default;
+
+    std::shared_ptr<TwitchUser> resolveID(const UserId &id)
+    {
+        TwitchUser u = {
+            .id = id.string,
+            .name = {},
+            .displayName = {},
+        };
+        return std::make_shared<TwitchUser>(u);
+    }
+};
+
+}  // namespace chatterino::mock