Refactor FXIOS [Nimbus] Update initial experiments JSON for Nimbus (#29062)

update initial_experiments.json based on the current first-run experiments in experimenter

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Author: github-actions[bot]

firefox-ios/Client/Experiments/initial_experiments.json

@@ -553,6 +553,71 @@
       "firefoxLabsDescriptionLinks": null,
       "firefoxLabsGroup": null,
       "requiresRestart": false
+    },
+    {
+      "schemaVersion": "1.12.0",
+      "slug": "shake-to-summarize-apple-intelligence-rollout",
+      "id": "shake-to-summarize-apple-intelligence-rollout",
+      "arguments": {},
+      "application": "org.mozilla.ios.Firefox",
+      "appName": "firefox_ios",
+      "appId": "org.mozilla.ios.Firefox",
+      "channel": "release",
+      "userFacingName": "Summarizer - Apple Intelligence Rollout",
+      "userFacingDescription": "Summarizer",
+      "isEnrollmentPaused": false,
+      "isRollout": true,
+      "bucketConfig": {
+        "randomizationUnit": "nimbus_id",
+        "namespace": "ios-apple-summarizer-feature-release-ios_apple_intelligence_available_user-rollout-1",
+        "start": 0,
+        "count": 10000,
+        "total": 10000
+      },
+      "featureIds": [
+        "apple-summarizer-feature"
+      ],
+      "probeSets": [],
+      "outcomes": [],
+      "branches": [
+        {
+          "slug": "control",
+          "ratio": 1,
+          "feature": {
+            "featureId": "this-is-included-for-mobile-pre-96-support",
+            "enabled": false,
+            "value": {}
+          },
+          "features": [
+            {
+              "featureId": "apple-summarizer-feature",
+              "enabled": true,
+              "value": {
+                "enabled": true,
+                "toolbarEntrypoint": true,
+                "shakeGesture": true
+              }
+            }
+          ]
+        }
+      ],
+      "targeting": "(is_apple_intelligence_available) && (app_version|versionCompare('143.!') >= 0) && (language in ['en'])",
+      "startDate": "2025-08-29",
+      "enrollmentEndDate": null,
+      "endDate": null,
+      "proposedDuration": 28,
+      "proposedEnrollment": 7,
+      "referenceBranch": "control",
+      "featureValidationOptOut": false,
+      "localizations": null,
+      "locales": null,
+      "publishedDate": "2025-08-29T19:27:24.903506Z",
+      "isFirefoxLabsOptIn": false,
+      "firefoxLabsTitle": "",
+      "firefoxLabsDescription": "",
+      "firefoxLabsDescriptionLinks": null,
+      "firefoxLabsGroup": "",
+      "requiresRestart": false
     }
   ]
 }