Overlap simulator boot with the rest of the iOS E2E setup

The iOS E2E action did all of its setup one step after another before
touching the simulator. `xcrun simctl install` then waited ~2 minutes for
the simulator to finish booting.

- Start booting the simulator as the first step (new `boot` subcommand
  of maestro-ios.js), so it boots while Maestro, Java, the node modules
  and Metro are being set up.
- Drop the `idb-companion` install. Maestro removed its IDB dependency on
  iOS in 1.x (see "Removed IDB on iOS" in its changelog) and 2.6.1 doesn't
  reference it.
- Drop the second Node.js setup: both callers (RNTester and the template
  app) already set up Node.js before using the action.

Author: cipolleschi

.github/actions/maestro-ios/action.yml

@@ -37,22 +37,23 @@ inputs:
 
 runs:
   using: composite
+  # Expects Node.js to be set up by the calling job.
   steps:
+    # Booting takes a couple of minutes; it finishes while the next steps run.
+    - name: Boot simulator
+      shell: bash
+      run: |
+        node .github/workflow-scripts/maestro-ios.js boot \
+          "${{ inputs.device-model }}" \
+          "${{ inputs.device-os }}"
     - name: Installing Maestro
       shell: bash
       run: export MAESTRO_VERSION=2.6.1; curl -Ls "https://get.maestro.mobile.dev" | bash
-    - name: Installing Maestro dependencies
-      shell: bash
-      run: |
-        brew tap facebook/fb
-        brew install facebook/fb/idb-companion
     - name: Set up JDK 17
       uses: actions/setup-java@v5
       with:
         java-version: '17'
         distribution: 'zulu'
-    - name: Setup node.js
-      uses: ./.github/actions/setup-node
     - name: Run yarn install
       uses: ./.github/actions/yarn-install
     - name: Start Metro in Debug

.github/workflow-scripts/maestro-ios.js

@@ -25,6 +25,11 @@ node maestro-ios.js <path to app> <app_id> <maestro_flow> <jsengine> <flavor> <w
 @param {string} deviceOS - Optional Maestro device OS, such as iOS-26-2
 @param {string} testStatePath - Optional file used to persist per-flow results between CI retries
 @param {string} excludeTags - Optional comma-separated flow tags to exclude
+
+node maestro-ios.js boot [device_model] [device_os]
+
+Starts booting the simulator the tests will run on and returns without
+waiting for the boot to finish.
 ==============
 `;
 
@@ -557,11 +562,24 @@ async function main(args = process.argv.slice(2)) {
   console.log('Test finished');
 }
 
+// Lets the workflow start the (slow) simulator boot before the rest of the
+// setup, instead of waiting for it in the middle of the test step.
+function boot(args) {
+  if (args.length > 2) {
+    throw new Error(`Invalid number of arguments.\n${usage}`);
+  }
+  launchSimulator(findAvailableSimulator(args[0] || null, args[1] || null));
+}
+
 if (require.main === module) {
-  main().catch(error => {
-    console.error(error);
-    process.exitCode = 1;
-  });
+  const args = process.argv.slice(2);
+  const command = args[0] === 'boot' ? () => boot(args.slice(1)) : main;
+  Promise.resolve()
+    .then(command)
+    .catch(error => {
+      console.error(error);
+      process.exitCode = 1;
+    });
 }
 
 module.exports = {