Add JSON files for Payment Gateway Interface and API documentation updates

- Created a new JSON file for the PaymentGatewayInterface.php, detailing its methods and return types.
- Added a JSON file for payment.md, documenting various API endpoints and their parameters, responses, and errors.
- Introduced a JSON file for fix-admin-modal-and-calendar.md, outlining issues and solutions related to admin modal and calendar functionalities.

graphify-out/.graphify_labels.json

@@ -653,6 +653,8 @@
   "651": "Community 651",
   "652": "Community 652",
   "653": "Community 653",
+  "654": "Community 654",
+  "655": "Community 655",
   "656": "Community 656",
   "657": "Community 657",
   "658": "Community 658",
@@ -661,6 +663,8 @@
   "661": "Community 661",
   "662": "Community 662",
   "663": "Community 663",
+  "664": "Community 664",
+  "665": "Community 665",
   "666": "Community 666",
   "667": "Community 667",
   "668": "Community 668",
@@ -668,7 +672,23 @@
   "670": "Community 670",
   "671": "Community 671",
   "672": "Community 672",
+  "673": "Community 673",
+  "674": "Community 674",
   "675": "Community 675",
   "676": "Community 676",
-  "679": "Community 679"
+  "677": "Community 677",
+  "678": "Community 678",
+  "679": "Community 679",
+  "680": "Community 680",
+  "681": "Community 681",
+  "682": "Community 682",
+  "683": "Community 683",
+  "684": "Community 684",
+  "685": "Community 685",
+  "686": "Community 686",
+  "687": "Community 687",
+  "688": "Community 688",
+  "689": "Community 689",
+  "690": "Community 690",
+  "691": "Community 691"
 }