Playerbot: BotGear addon — fix target guid extraction

The UnitGUID parser grabbed the realm/sub field (-(%d+)-%x+$) instead of the
low counter, so the request carried the owner's guid (1) and the server
resolved the owner, not the bot — FindConnectedPlayer + IsOwner both failed
and no GEAR response was ever sent. Parse the LAST '-' group as hex (the
character counter), and reset the title hint when no target resolves.

src/modules/PlayerbotV2/Addon/BotGear/BotGear.lua

@@ -55,7 +55,11 @@ local function ResolveTarget()
     if not UnitExists("target") then return nil, nil end
     local guid = UnitGUID("target")
     if not guid then return nil, nil end
-    local low = tonumber(string.match(guid, "-(%d+)-%x+$"))
+    -- Player guid format ends with the low counter as hex, e.g.
+    -- "Player-1-00000258" or "Player-0000-00000258" / "Player-0-1-00000258".
+    -- The character counter is the LAST '-' group (hex).
+    local low = tonumber(string.match(guid, "%-([%x]+)$"), 16)
+    if not low or low == 0 then return nil, nil end
     return low, UnitName("target")
 end
 
@@ -301,6 +305,10 @@ local function RefreshTarget()
             modelActor:SetUnit("target")
         end
         RefreshAll()
+    else
+        if frame and frame.title then
+            frame.title:SetText("Bot - /target a bot")
+        end
     end
 end