ci: run less e2e jobs when when running from PR (#1239)

## 📜 Description

Reduced amount of iOS e2e tests for PR.

## 💡 Motivation and Context

When we open PR we want to move as quick as possible. Running 2 build
jobs + 6 e2e jobs is a very expensive in terms of time (because we have
only 5 runners available to use simultaneously). So in this PR I decide
to use only 3 jobs for tests:
- iOS 15 (prior to this version only TextKit v1 was used, events were
more synchronous and we had less strange bugs and less strange events
were emitted);
- iOS 17 - classically broken iOS version. On this version we have
TextKit v2, we have early end events etc. +iOS 17 runner is running
fast, so it's our gold standard.
- iOS 26 + Xcode 26 - this is a new combination and we need to assure
that newest iOS runs without issues/regressions.

When we merge into main we run all 6 jobs (just for double
verification).

To achieve this I added a separate step that prepares a matrix for e2e
tests. I've tried other options but this was the only one that was
working 🤷‍♂️

## 📢 Changelog

<!-- High level overview of important changes -->
<!-- For example: fixed status bar manipulation; added new types
declarations; -->
<!-- If your changes don't affect one of platform/language below - then
remove this platform/language -->

### CI

- run only 3 iOS e2e for PRs;

## 🤔 How Has This Been Tested?

Tested manually via this PR.

## 📸 Screenshots (if appropriate):

<!-- Add screenshots/video if needed -->
<!-- That would be highly appreciated if you can add how it looked
before and after your changes -->

## 📝 Checklist

- [x] CI successfully passed
- [x] I added new mocks and corresponding unit-tests if library API was
changed

Author: kirillzyusko

.github/workflows/ios-e2e-test.yml

@@ -96,69 +96,31 @@ jobs:
         with:
           name: ios-e2e-ipa-xcode${{ matrix.config.xcode }}
           path: example/ios/build/Build/Products/Release-iphonesimulator/KeyboardControllerExample.app/**
+  determine-e2e-matrix:
+    name: ⚖️ Determine E2E Test Matrix
+    runs-on: ubuntu-latest
+    outputs:
+      matrix: ${{ steps.set-matrix.outputs.matrix }}
+    steps:
+      - name: Set matrix for PR or main
+        id: set-matrix
+        run: |
+          if [[ "${{ github.event_name }}" == "pull_request" ]]; then
+            # Subset for PRs: Only ios 15, 26, 26e (adjust as needed)
+            echo 'matrix={"devices": [{"ios": 15, artifact: "16.4", "xcode": "16.4", "macos": 15, "runtime": "15.5", "iphone": "iPhone 13 Pro", "os": "15.5"}, {"ios": 17, artifact: "16.4", "xcode": "16.4", "macos": 15, "runtime": "17.5", "iphone": "iPhone 15 Pro", "os": "17.5"}, {"ios": "26e", artifact: "26.1", "xcode": "26.1", "macos": 26, "iphone": "iPhone 16e", "os": "26.1"}]}' >> $GITHUB_OUTPUT
+          else
+            # Full set for main
+            echo 'matrix={"devices": [{"ios": 15, artifact: "16.4", "xcode": "16.4", "macos": 15, "runtime": "15.5", "iphone": "iPhone 13 Pro", "os": "15.5"}, {"ios": 16, artifact: "16.4", "xcode": "16.4", "macos": 15, "runtime": "16.4", "iphone": "iPhone 14 Pro", "os": "16.4"}, {"ios": 17, artifact: "16.4", "xcode": "16.4", "macos": 15, "runtime": "17.5", "iphone": "iPhone 15 Pro", "os": "17.5"}, {"ios": 18, artifact: "16.4", "xcode": "16.4", "macos": 15, "iphone": "iPhone 16 Pro", "os": "18.5"}, {"ios": 26, artifact: "16.4", "xcode": "26.0", "macos": 26, "iphone": "iPhone 17 Pro", "os": "26.0"}, {"ios": "26e", artifact: "26.1", "xcode": "26.1", "macos": 26, "iphone": "iPhone 16e", "os": "26.1"}]}' >> $GITHUB_OUTPUT
+          fi
   e2e-test:
-    name: ⚙️ Automated test cases (iOS-${{ matrix.devices.ios }}, XCode-${{ matrix.devices.xcode }})
+    name: ⚙️ Automated test cases (iOS-${{ matrix.devices.ios }}, XCode-${{ matrix.devices.artifact }})
     runs-on: macos-${{ matrix.devices.macos }}
     timeout-minutes: 90
     env:
       WORKING_DIRECTORY: example
     strategy:
-      matrix:
-        devices:
-          [
-            {
-              ios: 15,
-              artifact: "16.4",
-              xcode: "16.4",
-              macos: 15,
-              runtime: "15.5",
-              iphone: "iPhone 13 Pro",
-              os: "15.5",
-            },
-            {
-              ios: 16,
-              artifact: "16.4",
-              xcode: "16.4",
-              macos: 15,
-              runtime: "16.4",
-              iphone: "iPhone 14 Pro",
-              os: "16.4",
-            },
-            {
-              ios: 17,
-              artifact: "16.4",
-              xcode: "16.4",
-              macos: 15,
-              runtime: "17.5",
-              iphone: "iPhone 15 Pro",
-              os: "17.5",
-            },
-            {
-              ios: 18,
-              artifact: "16.4",
-              xcode: "16.4",
-              macos: 15,
-              iphone: "iPhone 16 Pro",
-              os: "18.5",
-            },
-            {
-              ios: 26,
-              artifact: "16.4",
-              xcode: "26.1",
-              macos: 26,
-              iphone: "iPhone 17 Pro",
-              os: "26.0",
-            },
-            {
-              ios: "26e",
-              artifact: "26.1",
-              xcode: "26.1",
-              macos: 26,
-              iphone: "iPhone 16e",
-              os: "26.1",
-            },
-          ]
-    needs: build
+      matrix: ${{ fromJson(needs.determine-e2e-matrix.outputs.matrix) }}
+    needs: [build, determine-e2e-matrix]
     steps:
       - uses: actions/checkout@v4
       - name: Download a single artifact