add the flag of Occitania (#3179)

If this PR fixes an issue, link it below. If not, delete these two
lines.
Resolves #(issue number)

## Description:

Add a flag : Occitania flag
<img width="1090" height="664" alt="image"
src="https://github.com/user-attachments/assets/6ad5eb7c-a8f1-4c61-995c-e4f0c6d71204"
/>

added the Occitania flag via the svg (same as the flags already in-game)
and added it to countries.json

## Please complete the following:

- [X] I have added screenshots for all UI updates
- [X] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [X] I have added relevant tests to the test directory
- [X] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced

## Please put your Discord username so you can be contacted if a bug or
regression is found:

young_la_flame

---------

Co-authored-by: Jules <swayle3@Jules.local>

resources/countries.json

@@ -1533,6 +1533,11 @@
     "continent": "Europe",
     "name": "Norway"
   },
+  {
+    "code": "1_Occitania",
+    "continent": "Europe",
+    "name": "Occitania"
+  },
   {
     "code": "Ohio",
     "continent": "North America",