refactor: v2 calendars busy-times (#18244)

* refactor: make dateFrom and dateTo required

* refactor: make dateFrom and dateTo required

* refactor: useCalendarsBusyTimes enabled only if dateFrom & dateTo passed

docs/api-reference/v2/openapi.json

@@ -3408,6 +3408,7 @@
       "get": {
         "operationId": "CalendarsController_getBusyTimes",
         "summary": "Get busy times",
+        "description": "Get busy times from a calendar. Example request URL is `https://api.cal.com/v2/calendars/busy-times?loggedInUsersTz=Europe%2FMadrid&dateFrom=2024-12-18&dateTo=2024-12-18&calendarsToLoad[0][credentialId]=135&calendarsToLoad[0][externalId]=skrauciz%40gmail.com`",
         "parameters": [
           {
             "name": "loggedInUsersTz",
@@ -3419,6 +3420,26 @@
               "type": "string"
             }
           },
+          {
+            "name": "dateFrom",
+            "required": false,
+            "in": "query",
+            "description": "The starting date for the busy times query",
+            "example": "2023-10-01",
+            "schema": {
+              "type": "string"
+            }
+          },
+          {
+            "name": "dateTo",
+            "required": false,
+            "in": "query",
+            "description": "The ending date for the busy times query",
+            "example": "2023-10-31",
+            "schema": {
+              "type": "string"
+            }
+          },
           {
             "name": "credentialId",
             "in": "query",